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Australian Radio Communications Industry Association Inc. (ARCIA)Unit 9 – 21 Huntingdale Road, Burwood, Vic 3125 Australia

www.arcia.org.au - @ARCIAorg – [email protected]

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ELECTRICAL EQUIPMENT FORHAZARDOUS AREAS [EEHA]A summary of requirements for selection of electrical equipment for use onhazardous sites oriented towards suppliers of portable electronic equipment.

ARCIA Electrical Equipment for Hazardous Areas (EEHA)

1 ARCIA 2016| ELECTRICAL EQUIPMENT for use in HAZARDOUS AREAS

Summary

Document Overview

During the reviewing of this document we identified a number of possible issues relating to theinterpretation of such a heavily technical document. One of the major issues was that the technicalnature of the regulations makes it look like we are trying to police the workplace.

We as vendors are simply offering advice; if the client already has foreign certified equipment and heis happy to use it then that is not an issue for the vendor. Our aim is that as radio industryprofessionals we give correct advice.

NOTE: Not all areas are hazardous even where fuel or chemical are involved, some chemicals andproducts like diesel are not considered explosive. Hazardous/explosive areas are often relativelysmall and usually highly controlled. In an airport for example the only normally applicable hazardsare around aircraft re-fuelling points, not the entire tarmac. Hence your engineers, baggagehandlers, catering staff and maintenance staff generally don’t need certified equipment (confirm thiswith the client, site rules vary significantly).

A customer may be using foreign certified equipment which may not immediately look to becorrectly certified. There are a multitude of reasons for this which may not be immediatelyapparent to the vendor and it does not mean that it is unsafe. Foreign certified equipment does nothave higher failure rates; it is simply not what is defined in regulations in Australia. Customers mayhave already done risk assessments on this or had it approved by other means.

We are not here to fix the client’s site hazards or change his/her way of working. We only want toavoid giving incorrect advice. The key seems to be to ask questions of the client,

“Does your site have any identified hazardous areas?” If so “What are your site hazards?” He/she may have predefined site requirements, a

hazardous area classification drawing or a list of hazardous materials: whatever the answerthen this document will help you understand the needs and correct protection levelsrequired for the equipment you offer.

“What are you preferences for levels of protection on electronic equipment?” If the clientdoesn’t know then this document will assist you in advising correctly.

The other issues we are trying to solve are:

If you have equipment and you don’t know if it is suitable for a specific hazard. If you sell foreign certified equipment, don’t panic many clients will still accept and there are

methods of having this accepted on some sites.

The important factor here is that the customer understands what they are accepting or you mightfind they blame you when the equipment proves unsuitable.

This document will not provide you enough information to re-evaluate the client’s hazardous areaclassification, that is a very specialised field. It will also not give you sufficient knowledge to changerisk assessments or equipment categories. You need to work with what the customer gives you andthis document is intended to show you how to interpret the information provided by the customerand give him professional sound advice on product selection.



Why is this Necessary?

There are Government regulations and workplace safety requirements designed to ensure that anyrisk to personnel is minimised and all of the risk factors are controlled. Without adherence to theseregulations and associated guidelines there is a possibility of loss of life, loss or destruction of assetsand resultant litigation.

Some radio users may need to use communications equipment in hazardous environments. It isimportant to understand the most hazards require the use of equipment which is certified as beingsafe for use in those hazards.

The EEHA (Electrical Equipment Hazardous Areas) regulations stem from the likelihood of heatand/or sparks from electrical equipment causing ignition of hazardous substances. There have beena number of methods or techniques developed to either protect against the possibility of ignition orto minimise the risk of ignition.

Australian standards are ANZEx; based on, and in many cases identical to the IECEx standards. IECExis a legally accepted form of compliance in Australia. ATEX (European) and US NEC certification,unless also tested to IECEx, is NOT accepted without professional assessment (see “Authorised useof Foreign Standards’ Compliant Equipment” Page 41)

Identifying the Hazard and Preventing Ignition

There are two (2) distinctly separate issues involved; one is the definition of the hazard and theother is the selection of a suitable protection mechanism to protect against igniting the hazards.The first step is to identify and define the actual hazard.

Area hazards are identified based on an assessment of risk of an explosion. Specific methods forassessment are defined in standards. Assessment is done by hazardous area assessors/inspectorsand apparatus to be used in hazardous areas are tested and certified to various levels bylaboratories approved under the standards regime.

The site assessors and the test laboratories are two (2) distinctly different entities. Manufacturerscannot test and issue certificates for their own equipment (except in ATEX; however this is NOTacceptable in Australia, more later on this topic).

Hazard Identification

The hazards (gas and/or dust) are identified and grouped relative to their explosivity and ignitiontemperature.

Hazards Classification is as follows:Degree of Risk (Zones)The likelihood or probability of the hazard occurring are defined as Zones (in the US system they arereferred to as Divisions). This identifies the likelihood of the hazard occurring, as below.

Zone 0 is an area in which an explosive gas atmosphere is present continuously or for long periods orfrequently

Zone 1 is an area in which an explosive gas atmosphere is likely to occur in normal operationoccasionally

Zone 2 is an area in which an explosive gas atmosphere is not likely to occur in normal operation but,if it does occur, it will exist for a short period only

Zone 20 is an area in which an explosive dust atmosphere, in the form of a cloud of dust in air, ispresent continuously, or for long periods or frequently.



Zone 21 is an area in which an explosive dust atmosphere, in the form of a cloud of dust in air, islikely to occur in normal operation occasionally.

Zone 22 is an area in which an explosive dust atmosphere, in the form of a cloud of dust in air, is notlikely to occur in normal operation but, if it does occur, will persist for a short period only.GroupsThe hazard is then divided into groups with similar attributes as below:

Mining: Group I Underground mines, typically IA as A is the subcategory for Methane(firedamp).

Gas: Group II Above ground Gas which is further subdivided in A, B or C based onexplosivity of the hazardous gas.

Dust: Group III Dust which is then also divided into sub-categories A, B or C based on theconductivity of the dust.

The hazardous materials are then further divided into sub-groups.

Gas and Dust Groups

Group IIA Propane

Group IIB Ethylene

Group IIC Hydrogen

Group IIIA Combustible flyings

Group IIIB Non-conductive dust

Group IIIC Conductive dustTemperature ClassThe hazard is then allocated a Temperature Classes.

This temperature group is based on the maximum temperature of equipment before ignition ispossible (with a safety margin).

The Temperature classes are as follows:

Temperature classrequired by the areaclassification

Ignition temperature of gas orvapour in °C

T1 >450°C

T2 >300°C

T3 >200°C

T4 >135°C

T5 >100°C

T6 >85°C

Note 1: Equipment with a higher “T” rating can be used in areas of lesser risk, e.g. a T6 device(suitable for a hazard ignition temperature of 85C can be used in a T1 area but not the reverse.

Note 2: Dusts are typically described with an actual Temperature, e.g. 135°C instead of a “T” Class.



The resultant hazardous area assessment and classification drawings give us the basis for selectingappropriately safe equipment.

E.g. a Zone 1 risk with above ground gas hazard of Ethylene Group IIB Gas hazard at ignitiontemperature of say T2 (actual ignition temperature 440°C meets T2 requirements).

Selection of Suitable Product

Select a technique that is suitable for the hazard from the table below. Some techniques are suitablefor some hazards and some are not.

Protection Techniques include Intrinsic Safety (I.S.)

There are a number of techniques used to protect electrical equipment in hazardous areas (EEHA) ofwhich Intrinsic Safety (Ex i) or sometimes referred to as “I.S.” equipment is only one. Intrinsic safetyis common in portable low powered equipment but don’t close your eyes to other techniques whichare becoming common.

Other Techniques that may be used

Gas

Zone

Technique Group Zone 0 Zone 1 Zone 2

Intrinsically Safe Ex ia II √ √ √

Intrinsically Safe Ex ib II √ √

Intrinsically Safe Ex ic II √

Encapsulation Ex ma II √ √ √

Encapsulation Ex mb II √ √

Flameproof Ex d II √ √

Increased Safety Ex e II √ √

Non Incendive Ex n II √

Powder Filling Ex q II √ √

Oil Immersion Ex o II √ √

Pressurised Ex p II √ √

Special Protection Ex s Subject to conditions of Certification – READ theCertificate

See next page for Dust techniques.



Or for Dust:

Zone


Intrinsically Safe Ex iaD III √ √ √

Intrinsically Safe Ex ibD III √ √

Intrinsically Safe Ex ic III √

Encapsulation Ex ma (or Ex mD) III √ √ √

Encapsulation Ex mb III √ √

Protection by Enclosure Ex tD A20 sometimes shownas “Ex ta”

III √ √ √

Protection by Enclosure Ex tD A21 sometimes shownas “Ex tb”

III √ √

Protection by Enclosure Ex tD B21 sometimes shownas “Ex tb”

III √ √

Protection by Enclosure Ex tD B22 sometimes shownas “Ex tc”

III √

Protection by Enclosure DIP A20 III √ √ √

Protection by Enclosure DIP A21 III √ √

Protection by Enclosure DIP B21 III √ √

Pressurised Ex pD III √ √

Then:

Select product which meets or exceeds ALL of the parameters for the defined hazard, i.e.

Zone (worst case) 0,1,2,20, 21 and/or 22. Above ground gas or dust or mining I, II or III. Gas and/or Dust sub-group, e.g. A,B or C. Temperature Class “T” rating (surface temperature must be less than ignition temperature

for specified hazard T1, T2, T3, T4, T5, T6 or specific actual temperature in °C.

NOTE: Equipment with higher levels of protection can be used in areas needing lesser protectionBUT all parameters must meet or exceed those of the hazard.

Example

If Propane is used in an above ground storage and processing facility it will typically (subject toreading of the hazardous area classification document) have some Zone 1 areas and some Zone 2areas.

The gas is identified as follows:

Propane (CH3CH2CH3) is defined as being Group IIA with an ignition temperature class for ignition is“T2” ignition temp 450°Crefer the following standard:

AS/NZS 60079.20.1:2012 IEC 60079-20-1, Ed. 1.0 (2010) Australian/New Zealand Standard Explosiveatmospheres Part 20.1: Material characteristics for gas and vapour classification—Test methods anddata.

If your product is intrinsically safe Ex i, then minimum product specification will be Ex ib IIC T2 Gb.



Where:

Ex = (Explosion protected) and

ia= Intrinsically Safe (suitable for Zone 0, 1, 2) or ib = Intrinsically safe (suitable for Zone 1 or Zone2)

IIA for Propane above ground.

“T2”Ignitiontemperature 450°C.(NOTE: T1 >450°C not equal to so we must take the higher level ofprotection.

Flowchart for selection purposes

Identify the HAZARD

Define the Zone and Gasor Dust Type

Establish the Group (egIIB or IIIC) and ignition

Temperature “T”

Select a SuitableProtection Technique

(eg Ex ib)

Select Equipment withAdequate ProtectionLevels for the Hazard

Inspect and MaintainAccording to

AS/NZS60079.17

Owner/OccupierHazardous Area

Classification Drawings

Customer Maintenanceand Inspection Progam

AustralianStandards (incl IECEx) or

Foreign

Deliver Equipment andCommission System/s

YES

Conformity AssessmentDocument

NO

FAIL PASS

Ex

Eg Zone1 II

Eg IIBEg ib or

ia

Eg ib IIC

Eg FMor ATEX



Table of Contents

Summary .................................................................................................................................................1

Document Overview ...........................................................................................................................1

Why is this Necessary?........................................................................................................................2

Identifying the Hazard and Preventing Ignition..................................................................................2

Hazard Identification.......................................................................................................................2

Selection of Suitable Product..........................................................................................................4

Overview ...........................................................................................................................................10

Ignition of hazardous materials ........................................................................................................11

Section 2: Classification of Hazardous Areas ........................................................................................13

Factors for Ignition............................................................................................................................13

Explosive limits (UEL/LEL) for gases and vapours .........................................................................13

Dusts .............................................................................................................................................13

How do we Define Hazardous Areas?...............................................................................................14

IECEx/ANZEx System in Australia ..................................................................................................14

Summary of Area Classification ....................................................................................................17

Section 3: Equipment Selection ............................................................................................................18

Hazardous Area Equipment Certification IECEx/ANZEx....................................................................18

Selecting Equipment .........................................................................................................................18

Methods of Avoiding Ignition .......................................................................................................18

Types of Protection Techniques....................................................................................................19

What is “intrinsic safety” (I.S.) ......................................................................................................19

Other Valid Techniques for Explosion Protection.........................................................................20

Other Certifications.......................................................................................................................22

General Requirements ..................................................................................................................22

Mixed Techniques .........................................................................................................................23

What Equipment is Suitable for Defined Hazard/s...........................................................................23

EPL Risk Assessment System.........................................................................................................25

Purpose of Certificates......................................................................................................................25

Marking .............................................................................................................................................26

Select the Right Equipment ..............................................................................................................26

Is the Equipment Suitable? ...............................................................................................................28

Section 4: The Global Standards Systems .............................................................................................29

Australia/New Zealand and others (IECEx and ANZEx)...............................................................29

IECEx..............................................................................................................................................29

US Classification System ...................................................................................................................30



USA (NEC 500/NEC505, UL, FM, IECEx, CSA, Others)....................................................................30

OSHA's Nationally Recognized Testing Laboratory (NRTL) Program ............................................31

US Hazardous Classification under NEC500 (NEC506 Area) is as follows: ........................................32

Class: Explosive Atmosphere ........................................................................................................32

US Hazardous Classification under NEC 505.....................................................................................33

Class Explosive Atmosphere: ........................................................................................................33

Zones (as Per IECEx) ......................................................................................................................33

Gas Group (Similar to IECEx) .........................................................................................................33

Temperature .................................................................................................................................33

USA System of Marking.................................................................................................................34

FM (Factory Mutual) and UL (Underwriters Laboratories) and Canadian Standards Associations(CSA) NEC 500 vs IECEx .....................................................................................................................35

Europe (ATEX ONLY)..........................................................................................................................35

Area Classification System ............................................................................................................37

ATEX Equipment Certification.......................................................................................................37

Comparison of Global Area Classification Systems...........................................................................38

Section 4: Australian Regulatory Framework .......................................................................................39

Legislation .........................................................................................................................................39

Site requirements – Equipment Records ..........................................................................................40

Verification Dossiers .....................................................................................................................40

Installation (and Supply) Records .................................................................................................40

Inspection Sheets..........................................................................................................................40

Authorised use of Foreign Standards’ Compliant Equipment ..........................................................41

Regulators – ......................................................................................................................................41

Who is Responsible? .........................................................................................................................41

Site Owner/Occupier.....................................................................................................................41

Plant Designers and Maintenance Staff.......................................................................................41

Installers........................................................................................................................................41

What are the ongoing compliance requirements?...........................................................................42

Inspections ....................................................................................................................................42

Service and Repair Requirements.................................................................................................42

Section 5: Handy Hints..........................................................................................................................43

Section 6: Appendices...........................................................................................................................44

APPENDIX A - Marking ......................................................................................................................44

APPENDIX B IECEx Member Bodies...................................................................................................45

IECEx Member Bodies ...................................................................................................................45

APPENDIX C: Standards.....................................................................................................................50

APPENDIX D: Regulatory Authorities ................................................................................................51



NSW...............................................................................................................................................51

VIC .................................................................................................................................................51

QLD................................................................................................................................................51

TAS ................................................................................................................................................51

SA ..................................................................................................................................................51

WA.................................................................................................................................................51

NT..................................................................................................................................................51

ACT ................................................................................................................................................51

APPENDIX E: Old Standards and Certificates ....................................................................................52

APPENDIX F: Frequently Asked Questions (FAQ’s) ...........................................................................53

Intrinsic Safety...............................................................................................................................53

Zones.............................................................................................................................................53

US Equipment Label (Marking) .....................................................................................................54

IECEX/ANZEx Marking/Labelling ...................................................................................................54

Label and Certificate not the same? .............................................................................................55

Fixed Radio System Equipment.....................................................................................................55

Change Batteries on Portable Equipment.....................................................................................55

Engrave or label equipment..........................................................................................................55

Regular Inspections.......................................................................................................................56

Foreign Certified Equipment.........................................................................................................56

Approval for Foreign Equipment, site specific ..............................................................................56

Repairers and Inspectors ..............................................................................................................56

Servicing and Repair......................................................................................................................57

Damaged Equipment ....................................................................................................................58

Inspectors......................................................................................................................................58

Radio Transmission, Ignition? .......................................................................................................58

Device (Apparatus) Certificate with a “U” Suffix ..........................................................................58

Device (Apparatus) Certificate with an “X” Suffix.........................................................................59

Power Limitation on Radios ..........................................................................................................59

Site Examples ....................................................................................................................................59

Mistakes ........................................................................................................................................60

Where do you find EEHA Assessors? ............................................................................................61

History...................................................................................................................................................63

Document version information ........................................................................................................... 63



Section 1: Why is Electrical Protection Necessary? What Causes Ignition?

When it goes wrong it can cause loss of life, loss of assets and litigation. It is regulated for thesereasons.

An example of what happens when it all goes wrong:

PIPER ALPHA RIG NORTH SEA 1988, 167 DIED, $US3.4 BILLION DOLLARS LOST AND THE END OF A MAJOR OIL

COMPANY.

Piper Alpha was a North Seaoil production platform operated by Occidental Petroleum (Caledonia) Ltd. Theplatform began production in 1976, first as an oil platform and then later converted to gas production. Anexplosion and the resulting oil and gas fires destroyed it on 6 July 1988, killing 167 men, with only 61 survivors.The death toll included two crewmen of a rescue vessel. The total insured loss was about £1.7 billion (US$3.4billion). At the time of the disaster, the platform accounted for approximately ten percent of North Sea oil andgas production, and the accident was the worst offshore oil disaster in terms of lives lost and industry impact.

From Wikipedia, the free encyclopaedia

Overview

The EEHA (Electrical Equipment Hazardous Areas) regulations stem from the likelihood of heatand/or sparks from electrical equipment causing ignition of hazardous substances. There have beena number of techniques developed to either protect against the possibility of ignition or to minimisethe risk of ignition. The hazards themselves have been segregated so that those of higher risk ofignition can be identified and adequate protection provided as well as identifying those of lesser riskwhich may be protected by less expensive means.

The Handbook (HB 13:2007) from Standards Australia defines this as follows:

“Where it is necessary to use electrical apparatus in an environment in which there may be anexplosion it is essential that measures are taken to eliminate the likelihood of an explosiveatmosphere occurring around any source of ignition or limiting the possibility of an ignition source,(e.g. arcs, sparks or hot surfaces) occurring.”

The Australian hazardous area standards for electrical equipment are called ANZEx and are closelybased on the international IECEx standards. You will see that the actual Australian and New Zealandstandards commonly have a reference to IEC standards, e.g. (IEC 60079-xx, Ed.x.x (20xx) MOD).

The “MOD” indicates the standard is modified from the original IEC document; typically this is due tospecific local regulations such as mains power supply voltages. The IEC document is bi-lingual; everysecond page is in French.

Australia is a member of the IEC and for many years and in fact an Australian, Mr Chris Agius is thesecretary of the IECEx scheme.



It is not uncommon to find equipment labelled (marked) with older AUSEx standards and approvals,this can be used indefinitely by the client if purchased prior to the expiry date of the certificate butcannot be sold as compliant by manufacturers or vendors after the expiry of the certificate seeAppendix C, Page 50.

Area hazards are regulated and specific standards are applied, assessment is done by hazardous areaassessors and apparatus are tested by approved laboratories such as TestSafe and SIMTARS here inAustralia, PTB, LCIE, Baseefa and SIRA in Europe, Factory Mutual and Underwriters Labs in the USA(when acting as certified IECEx laboratories) and CSA in Canada (also when acting as an IECExlaboratory).

The IECEx system which has been adopted by Australia has certifying bodies around the world. Mostcertifying bodies are also certifying bodies for other compliance schemes, even here in Australia, sodon’t take it for granted that a certificate from say TestSafe in Sydney is an IECEx or ANZEx certificateunless the equipment marking carry the IECEx or ANZEx identification).

NOTE 1: There are often references to EEHA inspectors and assessors variously throughout thisdocument. Probably the best term would be “advisors” if these services are used correctly. Thequalifications are defined in AS/NZS 4761.1:2008 “Competencies for working with electricalequipment for hazardous areas (EEHA) - Competency Standards“ and inspectors/assessors/advisorsmust have competencies in the appropriate tasks to perform the work. The titles are not necessarilyrelevant.

The Victorian regulators have “H” class inspection qualifications for EEHA which they add as afunction (to those qualified) to their mains power electrical inspectors. Most instruments and allportable equipment are low powered equipment and this association with the mains powerelectrical inspectors has become less relevant.

NOTE 2: Standards are constantly being upgraded please check that you are using the currentstandard and the latest revisions. Standards detailed in this document are current at the time ofwriting.

All standards have a suffix indicating the date of publishing, e.g. AS/NZS60079.0:2012 is the currentstandard; the 2012 suffix indicates the date of publishing. The only way to ensure that you havelatest standard (other than subscribing to the system, which is expensive) is to check at thewww.saiglobal.com for up to date versions.

Standards are constantly changing and evolving and sometimes these changes can be quitesignificant. Don’t rely on what was used last time as being correct this time. It is important howeverto note that changes in standards are NOT retrospective; so if the site owner purchased equipmentwhich as correctly certified at the time of purchase then he/she may continue use it. He/shehowever cannot purchase more of the same and put it into service if it is no longer correctlycertified.

In Australia and Europe and in fact all of the 33 IECEx affiliated countries “intrinsic safety” isdesignated “Ex i”. In the past a lot of US companies sold US certified equipment here and littleregulation applied to the use of foreign hazardous area electrical equipment and systems. Australiais now far more regulated and generally follows the European based system in fact even the USA hasnow accepted the European format along with its own unique original system, see NEC 505 Page 33.

Ignition of hazardous materials

With regards safety of equipment there are two (2) distinctly separate issues involved; one is thedefinition of the hazard and the other is the protection mechanism (called a technique) used toprotect the hardware (usually called “apparatus”).



A hazardous area is defined as an area in which an explosive atmosphere is present, or may beexpected to be present, in quantities such as to require special precautions for the construction,installation, and use of potential ignition sources.

The explosive atmosphere may be caused by the presence of a flammable liquid, gas or vapour or bythe presence of combustible dust in suspension or in layers or a combination of explosive gas anddust atmospheres.

Three basic conditions 1must be met for a fire or explosion to occur:

1 Flammable or combustible material must be present in sufficient quantities.

2 The material must be mixed with air or oxygen.

3 An ignition source of sufficient energy to raise the combustible material to its ignitiontemperature must be present.

By removing one or more of these conditions, ignition will not occur. This fact is the basis for all ofthe explosion protection techniques.

AIR/OXYGENCOMBUSTIBLE

MATERIAL

IGNITIONSOURCE

Figure 1: The Infernal Triangle

From an explosion protection perspective if we take away any one of these three (3) items then weremove the possibility of ignition.

All hazardous area protection techniques operate with the ability to exclude or control one or moreof these factors.

1 The exception is Explosives.



Section 2: Classification of Hazardous Areas

For us to control or prevent an explosion or fire we also need to define the area of likely hazard (ifany) and the type of explosive material or gas before we can define the level of protection neededand hence select product to operate safely in the specific location.

To do this all major standards, including ANZEx (Australia/New Zealand), IECEx (Global includingAustralia and New Zealand), NEC (USA), ATEX (European Union) break down the possible ignitionsources into groups as below:

Mining: Group I Underground mines are handled as a separate group. Underground mineshave additional unique hazards and are regulated somewhat differently.

Gas: Group II Above ground gas hazards are then further divided into Groups as definedby their susceptibility to Spark Ignition and Ignition Temperature.

Dust: Group III Dust is divided into Groups relative to the Conductivity of the dust andTemperature of Ignition.

To this point at least all international protection schemes have the same broad definition.

Factors for Ignition

Explosive limits (UEL/LEL) for gases and vapours

Before an explosion can occur there must be a mixture of the flammable gas or vapour with air. Sucha mixture is capable of exploding only when its concentration lies within certain limits.

These limits are known as the lower explosive limit (LEL) and the upper explosive limit(UEL) and areexpressed as percentages of the material mixed with air by volume.

Dusts

Dust explosion occur for one of two reasons, accumulation of dust on equipment where heatingcauses ignition and/or ignition of an explosive dust cloud in a manner similar to the ignition of anexplosive gas.

Combustible dusts are those dusts which are combustible or ignitable in mixtures with air in a similarmanner as the mix of gas with air (LEL and UEL parameters described above) but with dust theseparameters are not so easily defined. Many sources of ignitable dust produce considerable variancein particle size and hence the distribution in air may vary considerably over short periods of time(gravity being a factor).

Therefore dust is not similar to gas in terms of ignitability of the mixture when combined with air.Gas is relatively stable (UEL/LEL parameters) whereas dust changes as the various particle sizes fallout of the concentration due to gravity.

Dust explosions may be initiated by ignition of a cloud of dust. It is not unusual for an explosion tocause the dislodging of dust accumulated on local surfaces, leading to a further dust cloud explosion.

Site owners are responsible for defining the parameters of the substances in the hazardous areaassessment documents (not usually within the scope of the normal supply contracts as it is aspecialist and technically complex field usually unrelated to the equipment vendor’s expertise). It isrecommended that the specific dust characteristics are determined by laboratory tests as the size ofthe particles (which is relevant to the explosivity) will vary due to the way they are processed.Additionally a lot of dust hazards are from agricultural products (grain etc.) which do not haveconsistent size or moisture content



Since this document is aimed at an industry that largely provides portable or mobile equipment it isimportant to understand that while dust accumulations on the equipment may not be considered acritical factor as it would be with fixed motors and instruments, the portable apparatus is still asource of ignition for a dust cloud in the same way as it is a source of ignition for gases.

A common request of clients (to assessor/inspectors) is that “dust wont accumulate on my portableequipment therefore it doesn’t need certification” this is not valid, the equipment must be certifiedcorrectly if it is to be used in a hazardous area.

Portable equipment used in explosive dust atmospheres is still required to meet the same protectionlevels as fixed equipment, the excuse that the housekeeping2 is under control is NOT an exclusion tomeeting the standard.

In reality portable equipment is more likely to be near a dust cloud as the user of the apparatus mayinitiate the dust cloud by his/her own physical activity in the plant.

Explosive Dusts

Another issue worthy of mention is that explosive dusts (such as gunpowder, propellant powder andlead styphnate) are not considered in the normal manner as they may explode or ignite (gunpowderfor example “burns” and does NOT “explode” as some might assume) without oxygen.

How do we Define Hazardous Areas?

IMPORTANT NOTE: The classification of the hazardous area is the responsibility of the siteowner/occupier not the equipment vendor unless he/she has been contracted to perform the task.Hazardous Area Classification can only be done by trained and competent person as per Australianand New Zealand standard AS/NZS4761, as mentioned earlier in this document. The applicablestandards are:

GAS:AS/NZS 60079.10.1:2009Australian/New Zealand Standard™ Explosive atmospheres Part 10.1:Classification of areas—Explosive gas atmospheres(IEC 60079-10-1, Ed.1.0 (2008) MOD).

DUST:AS/NZS 60079.10.2:2011 Explosive atmospheres Part 10.2: Classification of areas—Combustible dust atmospheres IEC 60079-10-2 Ed.1.0 (2009).

Suppliers of hardware should ask the site owner/occupier what the hazards are on site and shouldobtain a clear definition from the purchaser as to the requirements.

Area classification is a method of analysing and classifying the environment where explosive gasatmospheres or combustible or explosive dusts might be present. This is to facilitate the properselection and installation of equipment to be used safely in that environment. The classificationtakes into account the ignition characteristics of the gas or vapour or dust/s such as ignition energy(gas/dust group) and ignition temperature (temperature class).

The result is a three (3) dimensional drawing and written description that clearly describes thehazard/s and the level of protection needed to operate safely and any identifiable special conditionsincluding housekeeping, maintenance, process checks and limits.

IECEx/ANZEx System in Australia

It is not uncommon for a site to have both dust and gas hazards in which case BOTH standards applyand electrical apparatus used on the site MUST meet the minimum requirements for ALL hazards.

2 NOTE: HOUSEKEEPING is the ability of the site owner operator to reduce the build-up of dust layers.Operational procedures are detailed in the hazardous area classification and if the “housekeeping” is adequatethen avoidance of dust build-up can reduce risk and therefore reduce the need for use of certified equipment.



Hazardous area classification is a complex technical task and a comprehensive review is consideredoutside of the scope of this document. A brief overview is included as background information only.

This will assist with understanding why different protection techniques are suitable for differenthazards.

GasArea of Hazard – Zones(Gas)Definition of the hazardous area is based on the possible sources of release (vents, flanges, fillpoints, valves, etc.) and the volume and pressure of release (called a grade of release).

It takes into account the explosivity of the gas as well as the relative density of the gas, i.e. lighter orheavier than air. It then considers the circumstances under which it may be expelled or releasedfrom containment under fault conditions AND under normal operating conditions.

The size of the zone/s depends on the estimated or calculated distance over which a hazard existsbefore it disperses to a concentration in air below its lower explosive limit (LEL) with an appropriatesafety factor. Often, if a clearly defined hazard exists in a building or other protected area then thewhole area will be classified as a single zone.

The standard defines these zones as follows:

Zone 0 is an area in which an explosive gas atmosphere is present continuously or for longperiods or frequently.

Zone 1 is an area in which an explosive gas atmosphere is likely to occur in normal operationoccasionally.

Zone 2 is an area in which an explosive gas atmosphere is not likely to occur in normaloperation but, if it does occur, it will exist for a short period only.

NH Non-hazardous. An area where no hazard exists under normal or abnormal operatingconditions.Gas Sub-Groups (Explosivity)

Having defined the actual area of the hazard the assessor then considers the explosivity of thehazardous material/s.

Gas types are listed in AS/NZS 60079.20.1:2012IEC 60079-20-1, Ed. 1.0 (2010)Australian/NewZealand Standard™ Explosive atmospheres Part 20.1: Material characteristics for gas and vapourclassification—Test methods and data.

This standard is a schedule of all known flammable gases and liquids and lists the ignitionparameters for each product.

AS/NZS60079.20 groups gases into three (3) main groups based on the energy required to ignitethem as below:

Group IIA Propane

Group IIB Ethylene

Group IIC Hydrogen

NOTE: The “II” pre-fix indicates that it is above ground and gas (not mining). Mining is “Group I” andthe suffix is “A” as methane (firedamp3) is the main gas group as shown above.

For example a Group I certified device is NOT suitable for a Group II application unless it has acertification for Group II.

3Firedamp is a gas that occurs naturally in coal seams. The gas is nearly always methane (CH 4) and is highlyinflammable and explosive when present in the air in a proportion of 5 to 14 percent.



Ignition temperature range “T” RatingIgnition temperature is a factor in the ignition of hazardous gases. In the Australian and IECExsystems gases are grouped under six (6) different temperature ratings or “T” Classes numbered 1 to6 as shown below:

Relationship between ignition temperature and "T" rating

Temperature class required bythe area classification

Ignition temperature of gas orvapour in °C

T1 >450°C

T2 >300°C

T3 >200°C

T4 >135°C

T5 >100°C

T6 >85°C

DustArea of Hazard – Zones (Dust)Dusts forms explosive atmospheres only at concentrations within the explosion range in a similarmanner to the LEL/UEL limits of gases BUT while a dust cloud with a very high concentration may notbe explosive, the danger exists if the concentration falls, it may enter the explosive range.

The hazards from dusts are twofold, the formation of a dust cloud from any source of release plusthe small continuous source of release, in time, is able to produce a potentially hazardous dust layer.The formation of dust layers, which may ignite due to self-heating or exposure to hot surfaces.

Area classification is based on a number of factors including:

Whether the dust is combustible. Dust combustibility can be confirmed by laboratory tests. Material characteristics for the process concerned. Nature of release from particular items of plant. Operational and maintenance regime for the plant, including housekeeping4.

Zones for dust (In Australia/NZ) are defined as: Zone 20, zone 21, zone 22 and non-hazardous asbelow.

Zone 20 is an area in which an explosive dust atmosphere, in the form of a cloud of dust inair, is present continuously, or for long periods or frequently.

Zone 21 is an area in which an explosive dust atmosphere, in the form of a cloud of dust inair, is likely to occur in normal operation occasionally.

4Housekeeping (DUST): Is the planned and current cleaning of dust hazard areas to negate or minimise the dust explosionhazard.

Both the regularity or frequency of cleaning and the effectiveness of this cleaning are important.

Thus, the presence and duration of a dust layer depends on the grade of release from the source of the dust, the rate atwhich it is deposited and the effectiveness of housekeeping (cleaning).

Three levels of housekeeping can be described as follows:

Good: Dust layers are kept to zero or negligible thickness irrespective of the grade of release.

Fair: Dust layers are not negligible the dust is removed before any fire can start.

Poor: Dust layers are not negligible and persist for more than one shift. The fire risk may be high.



Zone 22 is an area in which an explosive dust atmosphere, in the form of a cloud of dust inair, is not likely to occur in normal operation but, if it does occur, will persist for a shortperiod only.

NH Non-hazardous. An area where no hazard exists under normal or abnormal operatingconditionsDust Sub-Groups (Explosivity)

Due to the infinite number of possibilities with regards, particle size, moisture content and resistivitythere is no schedule of dusts as there is with gases. Dusts are assessed by either experience ofsimilar sites or more commonly through laboratory analysis.

The result of this assessment of the hazard the specific dust or dusts is the ability to group them intosub-categories in a similar way to gases, as below:

Group IIIA Combustible flyings

Group IIIB Non-conductive dust

Group IIIC Conductive dustTemperature “T” ClassFor dust Temperature class is usually expressed in actual °C.

Summary of Area Classification

The resultant drawings and supporting information from the Hazardous Area Classification(sometimes called “HAZLOC”) are placed in the verification dossier and reviewed and modified aschanges are made to the plant over time.

NOTE: These documents are NOT normally negotiable with supplier.

We can therefore define what level of hazard exists on a specific plant and parts thereof.

For Example: An area may be described as Zone 1 and 2 Gas hazard IIB Ethylene T 2. Equipment canthen be selected to meet or exceed the requirements for safe use in the defined hazard.

At this point we have identified extent and explosivity of the hazard, for example “IIB T4” or “IIA T6”.

Some purchasers will simply state the equipment hazard in this format. Group, Gas & TemperatureClass. E.g. Zone 1 and 2 Group IIB T4.

All hazardous locations in Australia will be assessed using the IECEx or equivalent standards. Foreignstandards are rarely used for site classification documents and if they are then it is the responsibilityof the owner occupier to translate this into Australian terms.

All area classification in Australia is done by local assessors to IECEx and ANZEx standards. Veryoccasionally a plant design originating from the EU or USA will form part of the site design but thisshould be translated into the Australian system by a competent hazardous area assessor.



Section 3: Equipment Selection

Hazardous Area Equipment Certification IECEx/ANZEx

The standards bodies or certification bodies (ExCB’s, previously called and still commonly referred toas ACB’s) appoint test laboratories called ExTL’s for the technical testing of equipment to be used inhazardous areas.

The test laboratories follow stringent guidelines on testing and certifying equipment includingongoing monitoring of quality assurance and regular audits of the manufacturing sites to ensureongoing compliance.

The test laboratories issue test reports to the ExCB’s and if the equipment meets the requirementsof the appropriate standards the ExCB’s issue Certificates of Conformity (CofC’s).

All ANZEx and IECEx certificates are in English.

Copies are available on line for ANZEx www.anzex.com.au for a fee and from IECEx, www.iecex.comfree of charge.

The certificate contains a considerable amount of valuable information including the level ofprotection and any special conditions of use including in many cases the acceptability of connectingaccessories and/or various equipment options. Make sure you get the latest revisions. This is easywith ANZEx and IECEx as all of the revisions are shown and you simply select the latest in the series ifmultiples are available.

Selecting Equipment

Methods of Avoiding Ignition

If we go back to the ignition triangle we can see that by removing one of the factors needed to causeignition then we can eliminate the risk of explosion or fire.

The different methods of protection can be summarized as follows:

Exclusion: This method involves the exclusion of the hazardous material, either gas or dust, from theapparatus so that a spark or hot surface inside the apparatus cannot cause ignition. Encapsulation(Ex m) is an exclusion technique.

Explosion containment: This method aims to contain an explosion, if it does occur, in the apparatus.A flameproof enclosure is probably the best known and most widely used of all techniques, but it isonly appropriate for gas hazards and only occasionally seen in portable equipment. Popular andeffective in electric motors but suitable only for Zone 1 and 2 Gas only.

Energy limitation: Flammable gases and combustible dusts have minimum ignition energies, belowwhich it is not possible for an arc or spark to cause an explosion.

If the energy in an electrical circuit can be maintained below these levels, it cannot cause anexplosion and is considered intrinsically safe, Ex i.

Dilution: This method involves dilution of a hazardous gas atmosphere below the LEL5 by ventilation.It is not appropriate for combustible dust areas. Ventilation (Ex v) is a technique using this methodmainly for site buildings.

5 LEL Lower Explosive Limit



Avoidance of ignition source: This method aims to prevent an ignition source from occurring. Themost common technique is increased safety. This is used for apparatus, or parts of apparatus such asterminal boxes, that will not arc or spark in normal service. Increased safety (Ex e) is a commontechnique using this method but limited to Gas only and Zones 1 and 2.

Types of Protection Techniques

These methods are the basis for the various explosion protection techniques. While intrinsic safetyis only one of the techniques it is the most common in terms of portable electronic equipment. It isa misnomer to call all explosion protected equipment “intrinsically safe” or “IS” and may lead toconfusion.

Each technique, see “Other Valid Techniques for Explosion Protection” , has a descriptor; “Exi”, “Ex n” “Ex d”, etc. This is important as the selection of equipment fit for the specific hazard relieson the selection of the correct technique for the type of hazard/s.

Not all techniques are suitable for all types of hazards. Some techniques are limited to Zone 2 orZone 1 and 2 and would not be suitable in a Zone 0 environment. Some techniques are suitable fordust (Group III) and not gas (Group II) and vice versa.

Multiple techniques may be used on an apparatus. This is common and acceptable only if thecertificate of compliance identifies the technique suitable for the application and the markingdescribes it as such.

What is “intrinsic safety” (I.S.)

This protection technique is based on limiting the amount of electrical energy in the “apparatus”(and includes interconnecting wiring exposed to the hazardous atmosphere) to below that which cancause ignition.

An Intrinsically safe “circuit” (commonly used for control and monitoring of instruments inhazardous areas) is a circuit in which any spark or thermal effect under normal operation andspecified fault conditions, cannot cause ignition of a specified explosive atmosphere.

Intrinsically safe “associated” apparatus are generally located in a safe area but are used to control(protect) remote intrinsically safe devices. They protect the hazardous area circuit from exposure toharmful voltages and/or currents from sources in safe areas, i.e. prevent inadvertently connectingsay a mains voltage to a hazardous area instrument.

“Associated apparatus” are usually barriers or isolators and have little relation to portableequipment except in the connection of accessories to the intrinsically safe portable device.

There are parameters for intrinsically safe “circuits” and “interconnecting cables” which areidentified on the apparatus certificate and the associated apparatus certificate. These parametersare critical to the safe operation of the apparatus and its associated circuitry. A competent personcan assess these parameters and advise as to the suitability. The parameters MUST be adhered tofor safety reasons.

Intrinsically safe equipment is divided into three (3) sub-categories based on the fault tolerance, i.e.the number of faults which can be applied before the protection technique fails, as below:

Ex ia Suitable for Zones 0, 1 and 2Ex ib Suitable for Zones 1 and 2Ex ic Suitable for Zone 2 ONLY

Intrinsic safety must also be separately identified if it is suitable for Dust. This is a new requirementand it is still common to intrinsically safe apparatus (Ex i) not specifically dust certified in dust hazardareas.



On the basis that the standards are NOT retrospective these products may remain in service untilend of life but the owner operate cannot purchase more for installation as new equipment.

Dust certified Ex i, intrinsically safe equipment MUST now have a “D” suffix added to the equipmenttechnique, e.g. Ex iaD or Ex ibD.

Simple Apparatus

AS/NZS 60079.11 allows the following apparatus to be considered simple apparatus:

Passive components, for example switches, junction boxes, resistors and simplesemiconductor devices.

Sources of stored energy with well-defined parameters, for example capacitors or inductors,whose values must be considered when determining the overall safety of the system.

Sources of generated energy, for example thermocouples and photocells, which do notgenerate more than 1.5V, 100mA and 25mW.

NOTE: This does NOT exempt these devices from meeting the general requirements ofAS/NZS60079.0 in terms of static discharge, dielectric strength, etc.

If you need to go down this path I suggest you get some professional advice, it’s not a “Simple” asthe title may indicate.

Special Conditions:

Intrinsically safe apparatus, like all other explosion protected equipment MUST adhere to any and all“special conditions” on the certificate.

Equipment which has special conditions which must be met have an “X” suffix in their certificatenumber.

Some examples of possible special conditions on portable equipment are as follows:

Must use leather carry case Must not be charged in hazardous areas Battery must NOT be removed in hazardous areas

Whatever the conditions are, they must be met. The condition will be written clearly in English onthe certificate of compliance.

Qualified service and repair by approved workshops and ongoing inspections are mandatory; seeService and Repair Requirements, Page 42.

Other Valid Techniques for Explosion Protection

As mentioned above, “Intrinsic Safety” is only one of a number of prescribed techniques forprotecting electrical equipment in hazardous areas. Obviously it is technically difficult (orimpossible) to design a high powered electric motor for example using energy limitation techniques.The descriptions below are summaries only due to space constraints; contact any EEHA assessor forfurther details.

Ex d Flameproof

This is a containment technique based on an enclosure which can withstand the pressure developedduring an internal explosion the pressure form which will escape through the specially designedflanges where it is cooled so as to have insufficient heat to ignite the surrounding atmosphere.

It is a technique suitable for gas only and is subject to some considerable installation rules.



Ex e – Increased Safety

The Ex e technique is one of avoidance of arcs or sparks or hot surfaces. This protection techniqueapplies measures to give increased security against the possibility of excessive temperatures and ofthe occurrence of arcs and sparks in normal service or under specified abnormal conditions.

Ex m – Encapsulation

Parts capable of igniting an explosive atmosphere by either sparking or heating are enclosed in acompound in such a way that the explosive atmosphere cannot be ignited under operating orinstallation conditions.

Encapsulation is an exclusion technique in that it prevents flammable gases from reaching apotential source of ignition within the encapsulated apparatus. The surface temperature of theencapsulated apparatus must not exceed the certified temperature classification.

The requirements for encapsulation compounds are very stringent and take into account all possiblefailure points for the encapsulants, i.e. heat, cold, water and fluids ingress, impact, etc.

Encapsulated apparatus may be used in Group I or II or III.

This is a technique that is likely to be found in portable equipment.

Ex n – Non-Sparking

Type of protection applied to electrical apparatus such that, in normal operation and in certainspecified abnormal conditions, it is not capable of igniting a surrounding explosive gas atmosphere.

It has no fault tolerance so is limited to Zone 2 areas only.

Only permitted in Zone 2 areas where the probability of a coincidence of an explosive mixture of gasand a fault in the apparatus is considered to be acceptably low.

Non-sparking is really a collection of various techniques and is slowly being replaced by other formsof protection. At one time Ex n had energy limited options but that has now been replaced byintrinsic safety Ex ic (Zone 2, no fault tolerance) although some old equipment marked Ex nL stillexists in the field.

This technique is sometimes found in portable radio equipment.

Ex o –Oil Immersion

A technique in which the electrical apparatus, or parts thereof, are immersed in a protective liquid.

Ex p –Pressurised Rooms and Enclosures

Enclosure in a protective gas maintained at a pressure greater than that of the external atmosphere.

Ex q –Powder Filling

Protection technique in which the parts capable of igniting a hazardous atmosphere are fixed inposition and completely surrounded by filling material; typically quartz or solid glass particles toprevent the ignition of an external explosive atmosphere.’

Ex s –Special Protection

This is a concept more so than a technique which has been adopted to permit the assessment andtesting of electrical apparatus which for technical, operational or functional reasons do not complywith the constructional or other requirements specified for apparatus with other types ofprotection. Not common and highly unlikely technique for portable equipment.



Ex v - Ventilation

Naturally or mechanically ventilated area where uncontaminated air is continuously introduced insufficient quantity to prevent formation of an explosive gas-air mixture.

Ex tD Protection by Enclosure Ex ‘tD’ (DIP) – Dust Ignition Protection

An Ex ‘tD’ previously called DIP (Dust Ignition Protection) is an enclosure sealed against dust and thesurface temperature must be maintained below the cloud or layer ignition temperatures of the dust.

Other Certifications

Component Certificates

The symbol “U” suffix to the certificate number indicates that the item is a component part that isincomplete and needs further evaluation prior to incorporation in Ex equipment. An apparatus witha certificate with the “U” suffix cannot be used in a hazardous area without further approval.

Associated Apparatus

Associated apparatus are usually located in a safe non-hazardous area (although they may have theirown certification as well) and are used to control intrinsically safe circuits where they connect tooutside equipment or power sources.

They are marked with square brackets e.g. [ia] which means suitable for connection to Zone 0(including Zone 1 and 2) hazardous area circuits but does NOT mean that it can be located in anyhazard, i.e. it must be installed in a safe area.

General Requirements

All explosion protected equipment regardless of the technique used must meet the generalconditions defined in AS/NZS60079:0. Each unique technique is then detailed in the appropriatestandard defining the technical parameters of that technique.

Following are some of the general requirements specified in AS/NZS 60079.0:

Enclosures made of plastic including the requirements for threaded holes in plastic. Avoidance of ignition due to static discharges. Light alloy enclosures including restrictions on the use of light alloys. Fasteners including special fasteners, designed to deter unauthorized access to enclosures. Earthing requirements. Specific requirements for rotating electrical machines. Plugs and socket outlets. Marking – The marking or Labelling on the certified equipment is critical, see above. Impact and drop tests. Ingress Protection requirements (IP Ratings). Torque tests. Temperature-rise tests. Thermal shock test. Insulation resistance of plastics parts. Non-metallic enclosures or parts, resistance to heat, cold, light, chemicals (Group 1).



Mixed Techniques

It is common for more than one technique to be used on a single apparatus. For example flameproofapparatus are often designed to also meet Ex ‘tD’ (DIP6) requirements by including gaskets in such away that they do not affect the flame paths.

What Equipment is Suitable for Defined Hazard/s

A summary below shows which equipment protection technique is suitable for which hazard.

From our hazardous area assessment we know the zone and gas group and temperature class of thelocation and hazard, now we can select suitable techniques from the list relative to the zoneclassification. For example, if we have Zone 0 hazard we are (ignoring “Ex s” as it is not common) weare able to select from “Ex ia” or “Ex ma”.

The equipment MARKING (which is critical to the device and must be correct and legible) will showEx for explosion protected.

Then the code for the technique, e.g. “ib” for zone 1 intrinsic safety.

Then the Group e.g. II for above ground GAS

Then sub-group GAS: say group B Ethylene

Then the “T” Class or maximum ignition temperature T1 to T6 OR the actual temperature e.g.T135°C.

So as an example a portable radio might have marking showing “Ex ib IIC T4” this means:

Explosion protected using intrinsic safety to Zone 1 and Zone 2 (not Zone 0) suitable for aboveground gas in the Hydrogen category (highest level and suitable for all below it) up to an ignitiontemperature of 135°C.

This product could NOT be used (unless there is additional marking) in a dust hazard or coal miningoperation or in a chemical plant where say Carbon Disulphide (a T6 gas) exists.

6 Dust Ignition Protection” an old technique now replaced by Ex tD. A lot of equipment is still in service in oldsilos and grain storage facilities.



Table 1: Equipment Protection Techniques vs GAS Zone Hazard

Zone


Intrinsically Safe Ex ia II √ √ √

Intrinsically Safe Ex ib II √ √

Intrinsically Safe Ex ic II √

Encapsulation Ex ma II √ √ √

Encapsulation Ex mb II √ √

Flameproof Ex d II √ √

Increased Safety Ex e II √ √

Non Incendive Ex n II √

Powder Filling Ex q II √ √

Oil Immersion Ex o II √ √

Pressurised Ex p II √ √

Special Protection Ex s Subject to conditions of Certification – READ theCertificate

Table 2: Equipment Protection Techniques vs DUST Zone Hazard

Zone


Intrinsically Safe Ex iaD III √ √ √

Intrinsically Safe Ex ibD III √ √

Intrinsically Safe Ex ic III √

Encapsulation Ex ma or Ex mD III √ √ √

Encapsulation Ex mb III √ √

Protection by Enclosure Ex tD A20 sometimes shownas “Ex ta”

III √ √ √

Protection by Enclosure Ex tD A21 sometimes shownas “Ex tb”

III √ √

Protection by Enclosure Ex tD B21 sometimes shownas “Ex tb”

III √ √

Protection by Enclosure Ex tD B22 sometimes shownas “Ex tc”

III √

Protection by Enclosure DIP A20 III √ √ √

Protection by Enclosure DIP A21 III √ √

Protection by Enclosure DIP B21 III √ √

Pressurised Ex pD III √ √



EPL Risk Assessment System

The recent concept of Equipment Protection Levels (EPL’s) for hazardous area electrical equipmentwas introduced in the 2009 editions of AS/NZS60070.10.0, AS/NZS60079.14 and AS/NZS60079.17.

It provides a mechanism for a site owner or hazardous area assessor to do a risk assessment on thelevel of protection provided by equipment.

Historically, as described in detail elsewhere in this document, equipment suitable for specific zoneapplications was based on the actual technique being used, some are deemed suitable for somezones and some are not, the system is/was quite rigid. The EPL system allows sufficiently competentpersons to include a risk assessment taking into account likelihood of ignition vs possible outcomes.

Risk adjustments for EPL are only to be applied by where a formal risk management and operationalframework have been established.

This use of ELP’s is a means of applying a risk assessment to operations which may not fit rigidly withthe conventional system. It is mentioned here as the EPL markings are now commonly shown on themarking for recently certified equipment and the terminology needs to be understood.

The normal relationship between EPL’s and Zone hazards is as follows:

Relationship between EPL's and Conventional Zones

Zone Equipment Protection Level (EPL)

0 Ga

1 Ga or Gb

2 Ga or Gb or Gc

20 Da

21 Da or Db

22 Da or Db or Dc

EPL’s can only be used to change these zone requirements if the site /owner can formally sign off thevariation.

Other FactorsRF RadiationRF transmissions from portable equipment are not considered dangerous within the parametersallowable under the power limitations governing intrinsically safe portable equipment, see, “RadioTransmission, Ignition?”Page58.

Purpose of Certificates

As quoted by the IEC website

“Certificates are used by different people for different reasons. The following is intended to captureall major uses:

1. By potential purchasers, to search the IECEx Database for a suitable product.

2. By the purchaser, to satisfy local regulatory bodies and insurers regarding an installation.

3. By the manufacturer, to satisfy local regulatory authorities regarding compliance of aproduct.



4. By the manufacturer, to satisfy his insurer regarding steps taken to avoid product liabilityclaims (however expressed in different countries).

5. By the manufacturer, as a marketing aid.

6. By the manufacturer, to identify which products are covered by the certificate.

7. By the certifier, to identify which products are covered by the certificate.

8. By the IECEx Scheme, to promote the scheme.

9. By the IECEx Scheme, as a source of revenue.

10. By the manufacturer, purchaser, installer and user of the equipment to transfer specificinformation needed for installation and use.”

Ref: Operational document No. IECEx OD 034

INTERNATIONAL ELECTROTECHNICAL COMMISSIONIEC SCHEME FOR CERTIFICATION TO STANDARDS FOR ELECTRICAL EQUIPMENT FOREXPLOSIVE ATMOSPHERES (IECEx System)

Marking

IMPORTANT: While there is considerable similarity between a lot of ATEX equipment and IECExequipment they are not interchangeable in terms of compliance. Some equipment is certified toboth schemes and this IS acceptable within the normal selection criteria. If in doubt the label (calledmarking) is the means of determining the approval.

If the marking does NOT say IECEx then it is NOT IECEx, regardless of whether the manufacturer saysit is or not. The Marking is critical.

The marking must describe the certificate Issuer, certificate number and the technique/s, group andtemperature class. THIS IS NOT OPTIONAL regardless of what the vendor or manufacturer says.

It is not uncommon for equipment to be certified to multiple standards and under multiple schemes;for example the NEC system AND the ATEX system AND the IECEx system, (this is entirely legal andacceptable).

If however the “marking” on the equipment says, for example ATEX and doesn’t show IECEx then it isNOT IECEx even though the manufacturer may say it is identical to the IECEx version. This is one ofthe most common issues EEHA assessors find. Importers bring in the wrong model (identical interms of specifications) and then try to pass it off as acceptable, this is NOT permissible and if theradio does NOT have the correct marking it is NOT approved.

Full details of the marking requirements as quoted from AS/NZS60079.0 as show in APPENDIX A -Marking, Page 44.

Select the Right Equipment

1. Identify the hazard and Zone from Hazardous area Classification drawingsand

2. Select a suitable technique for the hazard type from the gas and dust tablesand

3. select product with a protection level which meets or exceeds the hazardand

4. Abide by any conditions on the certificate of complianceand

5. Maintain and inspect it regularly.

See flowchart next page.



How to Select the Right Equipment

Identify the HAZARD

Define the Zone and Gasor Dust Type

Establish the Group (egIIB or IIIC) and ignition

Temperature “T”

Select a SuitableProtection Technique

(eg Ex ib)

Select Equipment withAdequate ProtectionLevels for the Hazard

Inspect and MaintainAccording to

AS/NZS60079.17

Owner/OccupierHazardous Area

Classification Drawings

Customer Maintenanceand Inspection Progam

AustralianStandards (incl IECEx) or

Foreign

Deliver Equipment andCommission System/s

YES

Conformity AssessmentDocument

NO

FAIL PASS

Ex

Eg Zone1 II

Eg IIBEg ib or

ia

Eg ib IIC

Eg FMor ATEX

Reading the Marking ANZEx/IECEx

E x ib I IC T 4 G b

E x =E xp lo s io nP r o te c t e d

T e c h n iq u eE x ib =

In t ri n s ic a l lys a f e

E P LG a , G b , G cD a , D b , D c

T ra t in gT 1 to T 6

M a y b eE x d , e , ia ,ib , ic , T a ,

e tc

IAO r

II A , II B II CO r

II IA , II IB ,II IC



Is the Equipment Suitable?

We’ve discussed all the attributes of various techniques and the levels of protection offeredincluding variables such as gas or dust, groups, above or below ground, coal mining and temperatureclass and how to identify the risks that may exist on a site, now most importantly we must translatethis into selecting the correct equipment.

If it is ANZEx or IECEx then it is relatively easy by reading the marking and certificate we can theneasily identify if a product is suitable for a defined hazard.

For example A plant with open areas where portable equipment are being used may bepredominantly Zone 2, IIA (above ground Propane) with a “T” rating of T3 (200°C ignitiontemperature) with some areas in close proximity to the process plant as Zone 1.

Equipment therefore must meet, as a minimum “Zone 1 IIA T3” (higher levels of protection aresuitable, e.g. IIB or IIC are acceptable, T4, T5 or T6 are also acceptable.

If it’s a foreign certified device then you will need professional help and the agreement of the siteowner/occupier to sign off an acceptance if the conformity assessment if it is positive.

If it fails then the only avenue is to ask an Ex TL (test lab) to certify it, cost can be around $100,000and takes up to a year. You will also need all of the manufacturer’s drawings and test data whichvery few will part with anyway. You will also need ongoing quality assurance audits at around$5,000-$10,000 per visit, twice annually. Not generally a good option.



Section 4: The Global Standards Systems

You will see below that there are considerable differences between the various systems especiallybetween the US system and the two European based systems (IECEx and ATEX). While all havehistorically proven safe it is sometimes difficult to make direct comparison between equipment fromvarious compliance regimes.

Fortunately most global instrument companies manufacture goods which are certified to all globalstandards. The communications industry has been slower to catch up but change has largely beenforced by the fact that it is illegal to use anything not ATEX certified in Europe. This is totallycontrolled in Europe. The US, while not accepting ATEX has moved to accept IECEx to bridge thegap. We are closer to a global system than ever before.

Australia/New Zealand and others (IECEx and ANZEx)

ANZEx is based closely on the IECEx scheme and the changes are largely those based on localdomestic electrical supply rules such as main power voltages. The exception is the Australian andNew Zealand have opted for a separate standard for



Servicing and Repair (see page 57), i.e. AS/NZS 3800 and competencies of personal are based onAS/NZS4761.

IECEx

Figure 2: IECEx Logo

See IECEx brochure “IECEx International Certification: The way to safety compliance in hazardousareas”

The quoted objective of the IECEx system is as follows:

“IECEx System Objective

The objective of the IECEx System is to facilitate international trade in equipment and services foruse in explosive atmospheres, while maintaining the required level of safety:

reduced testing and certification costs to manufacturer reduced time to market international confidence in the product assessment process one international database listing maintaining International Confidence in equipment and services covered by IECEx

Certification”

There are currently 33 countries as members of the IECEx scheme, see “

The image part with relationship ID rId27 was not found in the file.



APPENDIX B IECEx Member Bodies”, Page 45.

All of the applicable standards are shown in APPENDIX C: Standards, Page 50

Australia’s own national system ANZEx is based on the IECEx scheme. See www.anzex.com.au .ANZEx accepts the IECEx technical standards and certificates issue by IECEX ACB’s. The IECExscheme, as mentioned earlier has minor technical modifications (the standard has “MOD” on thetitle to reflect this) and the issue of an ANZEx certificate will include these country specific items.

Copies of certificates are, like IECEx certificates available but at a cost of $27.00 fromwww.anzex.com.au. The certificate description is available at no cost provides a means of checkingthe validity of the certificate but unfortunately does not include details or any special conditionswhich are mandatory as part of the compliance.

The ANZEx site does provide some access to old certificates and certificates issued under theprevious scheme, AUSEx for those working on older systems.

Reading the Marking ANZEx/IECEx

E x ib I IC T 4 G b

E x =E xp lo s io nP r o te c t e d

T e c h n iq u eE x ib =

In t ri n s ic a l lys a f e

E P LG a , G b , G cD a , D b , D c

T ra t in gT 1 to T 6

M a y b eE x d , e , ia ,ib , ic , T a ,

e tc

IAO r

II A , II B II CO r

II IA , II IB ,II IC

Is the Equipment Suitable?

US Classification System

USA (NEC 500/NEC505, UL, FM, IECEx, CSA, Others)

Figure 3: NEC Logo



Factory Mutual, Underwriter’s Laboratories Inc, CSA Labs and Intertek Testing Services NA, Inc. areall ExCB’s (Approved Certifying Bodies) under the IECEx scheme and can issue IECEx certificates inthe same manner as Australian IECEx certifying bodies. However the US retains its original countryspecific standards as below.

National Electrical Code (NEC) does not have specific standards for hardware or other apparatus itrelies on “Nationally Recognised Test Laboratories” (NRTL’s) such as Factory Mutual andUnderwriters Laboratories to test to their own standards and accept IECEx standards as well.

Equipment certified under the USA NEC 50 and NEC505 standards is not accepted here in Australiaand will require a conformity assessment from a competent assessor if he or she will issue a positivereport and if the site owner accepts it (See 41 ”Authorised use of Foreign Standards’ CompliantEquipment”, Page 41).

The NEC system is regulated by the United States Department of Labor Occupational Safety & HealthAdministration.

These private sector organisations perform certification for defined products to ensure that theymeet their specific published technical requirements. Each NRTL has their own test standards.These are used as the basis for testing and issuing certificates of compliance.

The following standards are recognised by OHSA for use in hazardous areas as well as the IECExstandards defined elsewhere in this document.

OSHA's Nationally Recognized Testing Laboratory (NRTL) Program

FM 3600 Electrical Equipment for Use in Hazardous (Classified) Locations, General Requirements

FM 3610Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II and III, Division 1Hazardous (Classified) Locations

FM 3611Electrical Equipment for Use in Class I, Division 2; Class II, Division 2; and Class III, Division 1and 2 Hazardous Locations

FM 3615 Explosion-proof Electrical Equipment, General Requirements

FM 3620 Purged and Pressurized Electrical Equipment for Hazardous (Classified) Locations

ISA 12.12.01Nonincendive Electrical Equipment for Use in Class I and II, Division 2 and Class III, Divisions 1and 2 Hazardous (Classified) Locations

UL 698A Industrial Control Panels Relating to Hazardous (Classified) Locations

UL 674 Electric Motors and Generators for Use in Hazardous (Classified) Locations

UL 783 Electric Flashlights and Lanterns for Use in Hazardous Locations, Class I, Group C & D

UL 823 Electric Heaters for Use in Hazardous (Classified) Locations

UL 844 Electric Lighting Fixtures for Use in Hazardous (Classified) Locations

UL 913Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division I,Hazardous (Classified) Locations

UL 1203Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous(Classified) Locations

USA NEC Article 500 (article 506 is the actual area classification standard) is the original and stillcurrently used CLASS/DIVISION system for hazardous area classification for equipment selection.



More recently (1996) the USA made a major shift towards global standardisation to more closelyalign to the rest of the world by introducing NEC Article 505 which introduces the European ZONEsystem of area classification.

Note that as mentioned in the overview, this is NOT related to the equipment testing laboratories,this is related to the regulations and the assessment of the hazard.

NEC 500 and NEC 505 hazard definitions are defined and updated by the US National Fire ProtectionAuthority (NFPA).



US Hazardous Classification under NEC500 (NEC506 Area) is as follows:

Class: Explosive Atmosphere

Class I – GAS

Class II – DUST

Class III – FLYINGS

Division: Degree of HazardDivision 1Where under normal operating conditions one or more of the following conditions are met:-

Ignitable concentrations of flammable gases, vapours or liquids are present continuously orfrequently.

Ignitable concentrations of combustible dusts are present. Easily ignitable fibres or materials producing combustible flyings are present.Division 2

Where under abnormal operating conditions one or more of the following conditions are met:-

Ignitable concentrations of flammable gases, vapours, or liquids are present within theatmosphere.

Ignitable concentrations of combustible dust are present within the atmosphere. Easily ignitable fibres or materials producing combustible flyings are present within the

atmosphere.Group (Gas or Dust) NOTE 1: The groups are NOT the same as IECEx.Group A Acetylene

Group B Hydrogen H2

Group C Ethylene

Group D Propane

Group E Metal Dusts

Group F Carbonaceous Dusts

Group G Combustible Dusts

NOTE 2: BE CAREFUL this is almost the REVERSE of the IECEx system Where “C” is the mostdangerous and “A” is the lesser.



Temperature Class

Temperature class required bythe area classification

Ignition temperature of gasor vapour in °C

T1 >450°C

T2 >300°C

T2A >280°C

T2B >260°C

T2C >230°C

T2D >215°C

T3 >200°C

T3A >180°C

T3B >165°C

T3C >160°C

T4 >135°C

T4A >120°C

T5 >100°C

T6 >85°C

Relationship between ignition temperature and "T" rating

This is the same for both NEC500 and NEC505 marking

US Hazardous Classification under NEC 505

The US NEC 505 scheme allows alignment of the US and IECEx (ANZEx) and ATEX Systems.

Class Explosive Atmosphere:

Class I = Gas or Vapour.

Class II = Dust environments.

Zones (as Per IECEx)

Zones 0, 1, 2, 20, 21, 22, see Area of Hazard – Zones(Gas) Page 15 and Area of Hazard – Zones(Dust)Page 16.

Gas Group (Similar to IECEx)

Mines are designated separately Group 1A as per IECEx and ATEX.

Acetylene Group IICHydrogen Group IIB+H2

Ethylene Group IIBPropane Group IIAMethane Group I MiningAbove Ground as per NEC 506

Temperature

As per temperature class table above.

Same as IECEx and ATEX but with additional sub-categories.



USA System of Marking

The NEC 500 is considerably different and does not directly translate to the Australian system

E x p lo s io n P r o o f f o r C la s s 1 ,D iv is io n 1 , G r o u p s A ,B ,C ,D T 5

T y p e o f P r o te c t io n( o p t io n a l E xc e p t f o r I . S .)

P e rm itt e dC la s s

( G a s 1 D u s t 2 )

P e rm itt e d D iv is io n( O p t io n a l E x c e p t f o r

D iv is io n 2 )P e rm itt e d G r o u p s

T e m p e r a t u r e C la s s( T 5 & T 6 O p tio n a l)

G r o u p A A c e t y le n e

G r o u p B H y d r o g e n H 2

G r o u p C Et h y l e n e

G r o u p D P r o p an e

G r o u p E M e t a l D u s t s

G r o u p FC a r b o n a c e o u s D u st s

G r o u p G C o m b u st i b l eD u st s

USA NEC 500 Equipment Marking

NEC 505/506 systems are more closely related to IECEx/ANZEx

Class I Zone 1 AEx d IIC T5 Gb

Type of ProtectionPermitted

Class(Gas I Dust II)

Permitted Groups

Temperature Class

Group IIA Acetylene

Group IIB HydrogenH2

Group IIC Ethylene

Group IID Propane

Group IIIC Metal Dusts

Group IIIB NonConductive andCarbonaceous Dusts

Group IIIA Fibres andFilings

PermittedZone

Explosion Protected EPL

Very ImportantUS System is the reverse of the

IEC for gas and Dust grouping, inIECEx and ATEX. A is least C is

worst reverse applies in USSystem

US NEC 505/506 Equipment Marking



FM (Factory Mutual) and UL (Underwriters Laboratories) and CanadianStandards Associations (CSA) NEC 500 vs IECEx

NOTE that FM Approvals (or UL or CSA) in this instance refers to testing to the USA National ElectricCode (NEC) standards ONLY.

Where FM Global or CSA or UL issue IECEx certificates of compliance then they are totally acceptableas IECEx certified devices.

It must be remembered that these labs are approved under both schemes.

It is the testing of NEC 500/505 schemes equipment vs the testing of IECEx certified equipmentwhich his different. FM, CSA and UL are approved IECEx certifying bodies (ExCB’s) in the IECExscheme. Their certificates for IECEx certified equipment are acceptable in the same way as acertificates from say TestSafe or SIMTARs are acceptable here. In this instance they are no differentto any other IECEx ExCB.

Europe (ATEX ONLY)

ATEX is an abbreviation from French‘ATmosphères EXplosibles’.

Until 1976 the European Union (EU) applied the Cenelec7 standards for technical compliance in whatis now called the “Old Approach”.

Manufacturers of electrical equipment for use in explosive atmospheres followed a voluntaryproduct compliance and certification procedure based on the European Community directives76/117/EEC, 79/196/EEC and 82/130/EEC.

It was the responsibility of each EU country to implement the necessary regulations and to appointtest laboratories known as “Notified Bodies” to undertake the conformity assessment proceduresspecified in the directives.

The directives were amended a number of times after 1976 to introduce new Harmonised Europeanstandards reflecting the state-of-the-art in the design and construction of explosion protectedelectrical equipment.

The distinctive mark was applied to the product to indicate that it could be sold within the EUwithout further controls.

ATEX Logo

Surveillance(Quality Audits)

The directives required that ongoing quality inspections of manufacture be undertaken periodicallyto ensure that the certified product continued to comply with the directive and manufactured inaccordance with the Certificate of Conformity.

7 CENELEC is the European Committee for Electrotechnical Standardization and is responsible forstandardization in the electrotechnical engineering field. CENELEC prepares voluntary standards, which helpfacilitate trade between countries, create new markets, cut compliance costs and support the development ofa Single European Market.CENELEC creates market access at European level but also at international level, adopting internationalstandards wherever possible, through its close collaboration with the International ElectrotechnicalCommission (IEC), under the Dresden Agreement.








Europe (ATEX ONLY)







ATEX Logo











Europe (ATEX ONLY)







ATEX Logo






The surveillance requirements were not interpreted uniformly among the various states and hencecannot be relied upon to equate to the IECEx standards applied here in Australia.

‘New Approach’

In 1985 the European Community agreed to a ‘New Approach’ to the certification of products inorder to facilitate free movement of goods within the European Union and overcome thediscrepancies between individual states resulting from different interpretations of the ongoingquality assurance and manufacturing inspections.

Assessment procedures include the CE marking as well as addressing separately the issues related tounderground mining equipment (Group I) and included dust as a separate compliance area.

This is one of the differences, ATEX include mechanical and RFI regulations whereas the US and IECExsystems are generally limited to electrical characteristics and anti-static.

The Compliance Deadline In July 2003 for meeting the requirements of Directive 94/9/ (ATEX 100a,now called ATEX 95) all equipment used in hazardous areas was mandated to be compliant with theNew Approach. Equipment could no longer be placed on the market with a Certificate of Conformityissued under the ‘old approach’.

The ATEX approach is to define Essential Health and Safety Requirements (EHSRs) and not specificstandards although there are “harmonised standards” which are acceptable. Application ofharmonised standards or other technical specifications remain voluntary, and manufacturers arefree to choose any technical solution that provides compliance with the EHSR’s.

This vague definition of technical standards and the use laboratories for testing which may not bepart of our acceptance scheme is the major issue with regards acceptance of these compliancecertificates. We, in the Australian system cannot accept the testing to an undefined or unrecognisedstandard.

Fortunately the “EN” (European Normative) versions of the IEC60079.xxxx series standards are thesame as the standards used here in Australia (through IECEx) and a large percentage of theequipment certified to ATEX has taken the path of compliance using standards which are acceptableto us in Australia. This DOES NOT gain compliance but gives an assessor something to work with interms of supporting evidence for a CAD document.

Acceptance of ATEX standards requires an assessment from a qualified EEHA assessor in Australia.Note that acceptance is NOT guaranteed and opinions vary. Some assessors won’t accept foreignstandards at all.

The use of ATEX certified equipment in Australia therefore needs a Conformity AssessmentDocument (CAD) from a qualified HA Inspector.

Vendors should be made aware that many laboratories certifying ATEX equipment are also IECExExCB’s and often both compliance test can be carries out at the same time to save time and money.

Some other very notable differences apply to use of ATEX equipment, for example Zone 2equipment under ATEX is approved for use with a manufacturer’s declaration and this is NOTaccepted here in Australia where third party testing is a mandatory part of compliance.



Area Classification System

This additional label information is often confusing when selecting equipment (be careful of theinterpretation) although ATEX uses the same EPL risk assessment system for selection of equipment.

Note the categorisation of Zones….

Category 1 = Zone 0

Category 2 = Zone 1

Category 3 = Zone 2

One of the reasons for this additional marking is that equipment technical compliance and qualityassurance procedures are not necessarily based on harmonised or IECEx standards.

ATEX Equipment Certification

The ATEX system is similar to the IECEx system in this regard except that the products carryadditional labelling.

All ATEX EC-Type Examination Certificates are issued in respect of conformity with the EuropeanUnion “Essential Health and Safety Requirements”(EHSRs). Some approved certifying bodies of ATEXequipment (called “Notified Bodies”) are partners in the IECEx scheme, some are not.

Certain standards are designated as “harmonised” and this includes almost the entire IECEx 60079.xxseries standards we use.

The ATEX system of product marking and identification is almost identical to the IECEX system butwith additional information which is sometime confusing.

There are several issues with acceptance of ATEX certified equipment for use in Australia:

NOT all equipment is certified to what are called “harmonised” standards. There are othermethods of obtaining technical conformity to ATEX and the other methods may NOT beacceptable in Australia as they MAY NOT be the same as our technical compliancerequirements.

ATEX allow self-assessment for Zone 2 products which is NOT acceptable in Australia orunder the IECEx/ANZEx guidelines.

Not all ATEX test laboratories are affiliated with the IECEx scheme. If a test laboratory is notpart of the IECEx system (including ANZEx) we limited ability to assess the laboratories’capabilities, expertise and/or quality systems.

ATEX certified devices are therefore not immediately accepted as suitable here in this country.

Product labelling (marking) on ATEX equipment has additional information including some which canbe confusing to the inexperienced person selecting equipment, see drawing on the next page.

The area classification system and zone, gas, group and temperature class information is the same asIECEX and ANZEx.

ATEX - Similar to IECEx but not quite the same.



ATEX Equipment Marking

Ex ib IIC T4 Gb

Ex =ExplosionProtected

TechniqueEx ib =

Intrinsicallysafe

EPLGa, Gb, GcDa, Db, Dc

T ratingT1 to T6

May beEx d, e ia,ib, ic, Ta,

etc

IAOr

IIA, IIB IICOr

IIIA, IIIB,IIIC

CE 1180 II 2 GATEX Carries thisadditional info

ExplosionProtection

Logo

CE Mark(Mandatory)

Notified BodyNo:

ie Number ofTest

Laboratory

Equipment GroupI for mines

II for other than mines

2 – Category1 For Zone 0 or 202 for Zone 1 or 213 for Zone 2 or 22

Gas (G)and or

Dust (D)

Comparison of Global Area Classification Systems

IECEx &ATEX Zone versus USA NEC Division Area Classification

Flammable MaterialPresent Regularly

Flammable MaterialPresent Intermittently

Flammable MaterialPresent abnormally

IECEX Zone 0 Zone 1 Zone 2

ATEX Category 1, Zone 0 Category 2, Zone 1 Category 3, Zone 2

USA NEC 500 Division 1 Division 2

USA NEC 505/506 Zone 0 Zone 1 Zone 2

Comparison of International Standards

JUST REMEMBER: IECEx Zone 0, 1 and 2, USA NEC 500 Division 1 and 2, ATEX Categories 1, 2, and 3.

ATEX ≠IECEX = ANZEx

NOTE: The US system described Zone 2 as “hazard being present abnormally or under abnormalconditions where IECEx system describes it as “an area in which an explosive gas atmosphere is notlikely to occur in normal operation but, if it does occur, it will exist for a short period only”. Thedifference is in terminology not necessarily the meaning.



Section 4: Australian Regulatory Framework

Installations in hazardous areas in Australia are controlled and legislated under the various stateelectricity acts as part of legislation controlling the installation of electrical equipment. The maintechnical reference for electrical installation in Australia is the Australian and New Zealand standardAS/NZS3000 which encompasses the hazardous area electrical installation requirements forexplosive environments.

Some electricity suppliers will not connect mains power to the site if there is no current, completeVerification Dossiers (see “Verification Dossiers” below): see Energy Australia Customer InstallationAdvice No. 1050 B 7/7/2006, copy attached.

Legislation

AS/NZS 3000:2007Australian/New Zealand Standard™ Electrical installations(known as theAustralian/New Zealand Wiring Rules) is referenced in law in all parts of Australia under the variouselectrical acts and work safety regulations. The standard defines the methods, rules, regulations andtechnical parameters for electrical installations in Australia and New Zealand.

Clause 7.7 HAZARDOUS AREAS (EXPLOSIVE GAS OR COMBUSTIBLE DUSTS), of AS/NZS3000:2007states:

7.7.1 Scope

The particular requirements of this Clause 7.7 apply to the selection of electrical equipmentand its Installation to ensure safe use in areas where flammable or combustible materials areproduced,

Clause 7.7.2.4.1 Selection goes on to state:

Electrical equipment selected for use in hazardous areas shall comply with the appropriaterequirements as specified in AS/NZS 60079.14.”

AS/NZS 60079.14:2009 states:

“The objective of this Standard is to set out the requirements for the design, selection anderection of electrical installations in hazardous areas associated with explosive atmospheres;these requirements are in addition to the requirements for electrical installations innonhazardous areas.”

The Standard’s handbook HB-13:2007 (a good reference document for issues relating to explosionprotection of electrical equipment without the need to reference the long and complex individualstandards) says:

“It is important to establish early in the process of classification of an area and selection of apparatuswho bears the responsibility for making the correct choices. It is the owner/occupier since the ownerof the property may not be the occupier. The owner/occupier may delegate the responsibility forclassifying an area, but the owner/occupier must ensure that the delegated person is competent tocarry out the task.

Any legal responsibility in Australia and New Zealand stems from an Act of Parliament. Theresponsibility may be spelt out in the Act, or in associated Regulations, or in a document called up bythe Act or Regulations.

Each Act may have a set of associated Regulations and provision for these Regulations is generallymade in the Act. Regulations are generally drawn up by the department administering the Act.”



“For hazardous areas, the relevant Acts and Regulations fit very definitely into two areas:underground coal mining and other industries. For both areas the Occupational Health and SafetyAct of the various States may be the overarching legislation.

2.2 UNDERGROUND COAL MINING

Regulations covering coal mining are the responsibility of the State in which the mining isundertaken. The object of the Regulations is to require mine and plant managers to develop andimplement systems to ensure that the workplace is safe and a safe system of working is employed.

The Regulations are no longer prescriptive but are performance based. They set out responsibilitiesand requirements of employers and employees, and may call up Australian Standards, such as theapparatus Standards.”

Site requirements – Equipment Records

Verification Dossiers

A file called a verification dossier is compiled for all hazardous sites. It is a listing all of theparameters of all of the hazardous area electrical equipment including interconnection drawings,protective barriers (where used) hazardous area classification drawings for the entire site andmaintenance records for all inspections and repairs.

This verification dossier is the responsibility of the site owner/occupier and must be available forinspection by regulatory bodies. It is not the responsibility of the vendor unless he elects to do thisas part of his/her contract of supply.

Clause 4.2 of AS/NZS60079.14 states:

“4.2 Documentation

It is necessary to ensure that any installation complies with the appropriate certificates as well aswith this Standard and any other requirements specific to the plant on which the installation takesplace. To achieve this result, a verification dossier shall be prepared for every installation and shall beeither kept on the premises or stored in another location. In the latter case, a document shall be lefton the premises indicating who the owner or owners are and where that information is kept, so thatwhen required, copies may be obtained.”

Installation (and Supply) Records

The periodic inspections should be done by someone other than the installer and the regularity ofthese inspections is based on the number of failures found in previous inspections.

Inspection sheets can only be completed by someone competent under AS/NZS60079.17 (the actualcompetencies are described in AS/NZS 4761).

Do NOT service or repair equipment if not deemed competent to do so or the compliance of theequipment will be compromised and the certification for that apparatus will be invalid.

If the equipment is certified under a foreign certificate then the CAD document approving its useshould be referred to in the inspection sheet.

Inspection Sheets

Electrical equipment used in hazardous areas must be inspected regularly and after being serviced orrepaired. Copies of sample inspection sheets are attached for reference and greater detail can befound in AS/NZS60079:17, the relevant inspection details for intrinsically safe equipment as found inPage 20 Table 2 – Inspection schedule for Ex “i”, “iD” and “nL” installations.



There are three (3) types of inspections; “Visual”, “Close” and “Detailed” as described in thestandard. Many of the inspection requirements are not relevant to portable equipment butinspections are nonetheless important and mandatory.

Authorised use of Foreign Standards’ Compliant Equipment

Conformity Assessment Documents (CAD’s) sometimes this is referred to as a “Letter of NOObjection” are documents prepared by a competent hazardous area inspector/assessor whoassesses the conformity of the foreign certified equipment against the local standard.

The assessor, when writing the report, will consider the local site hazards and area classification.He/she will also compare testing regimes between the foreign certifying body and the localregulations under AS/NZS60079.14 and AS/NZS60079.0 (including any specific requirements relatingto the explosion protection technique). The assessor may apply a risk assessment using the EPLsystem where definitions are inconclusive.

NOTE 1: Conformity assessments are site and hazard specific; there is NO blanket conformityassessment. General equipment certification for multiple sites and applications would requirelaboratory testing and the issuing of a new certificate of compliance.

NOTE 2: A reason for using the foreign certified equipment must be shown and it cannot be cost. Ifthere is a suitably certified piece of equipment meeting the functional needs and operationalrequirements of the site it should be used. The use of CAD’s is meant to meet the site needs whereno other types of equipment are suitable.

Regulators –

See “APPENDIX D: Regulatory Authorities, Page51

Who is Responsible?

Site Owner/Occupier

The entity legally responsible is described as the owner/occupier and is the operator of the site withmanagement function for the plant’s operations

Plant Designers and Maintenance Staff

Electrical equipment and installations in hazardous are designed to make them safe for operation insuch atmospheres. It is essential for reasons of safety that these safety features are notcompromised. They therefore require initial inspection and either:

Maintenance and regular periodic inspections or continuous supervision 8by skilledpersonnel in accordance with the standard are mandatory.

Installers

Persons working with electrical equipment in or on hazardous area sites must have competencies asdefined in AS/NZS4761 for the specific hazardous area work.

8Continuous supervision is quoted as “frequent attendance, inspection, service, care and maintenance of the electricalinstallation by skilled personnel who have experience in the specific installation and its environment in order to maintainthe explosion protection features of the installation in satisfactory condition.”



What are the ongoing compliance requirements?

Inspections

AS/NZS 60079.17 Clause 4.4.3 Moveable equipment, states

“Movable electrical equipment (hand-held, portable, and transportable) is particularly prone todamage or misuse and therefore the interval between periodic inspections may need to be reduced.Movable electrical equipment shall be submitted to a close inspection at least every 12 months.Enclosures which are frequently opened (such as battery housings) shall be given a detailedinspection at least every 6 months. In addition, the equipment shall be visually checked by the user,before use, to ensure that the equipment is not obviously damaged.”

Service and Repair Requirements

ANZEx certified equipment technically must be serviced and repaired by an AS/NZS3800 compliantworkshop. The manufacturer must also have this accreditation to repair the equipment if he/she isto perform the repair work. The common acceptance of IECEx rules effectively means that weaccept the IECEx standard which in this case is not the same. The Australian and New ZealandStandard is AS/NZS3800 while the IECEX standard is IEC 60079.19.

Quote from IECEx website as below:

“IECEx Certificates of Conformity are issued by approved IECEx Certification Bodies (ExCBs). An IECExCertificate of Conformity attests that a Service Facility, described on the Certificate, has beenindependently assessed and found to have appropriate equipment, competent staff and operateprocedures that provide confidence that the repair, overhaul or modification work complies withIECEx requirements, including IEC 60079-19. It also attests that the Service Facility’s site has beenaudited to verify that the Service Facility’s quality system meets IECEx requirements, specified inIECEx Operational Document OD 014.”

A list of accredited workshop can be found at http://iecex.iec.ch/iecex/iecexcsf.nsf/welcome

If equipment is serviced outside of the approved workshops it will compromise the certificate ofcompliance. Repaired equipment should also be given a “detailed9” inspection as per therequirements of AS/NZS60079.17 and IEC 60079.17 as per clause 4.3 Inspections, 4.3.1 General.

Therefore we can safely assume that the use of either AS/NZS3800 OR IEC 60079.19 applies toservicing but whichever way we look at it DON’T service equipment without competency to do sounder at least one of the applicable standards.

9 There are three (3) type of inspections defined in AS/NZS60079.17, “Visual”, “Close” and “Detailed”.



Section 5: Handy Hints

Most customers will appreciate a simple assessment of the hazard (typically quoted from theirdocument) and how you have identified the correctly certified equipment as part of your proposal.

A simple form based on one we use is shown below:

Client[Sample Client Pty Ltd]

Project/Job[Your Ref]

Area Hazard[eg Oil Terminal using Propane and Petrol, IIA]

"T" Class[Eg T2]

Ref: [Refer to customer/client HAC Dwgs ornotes] Document

Ref: Quote_Hazloc Rev#4

Special Considerations

[Add in any comments or considerations, e.g. if the ambient temperature is high as in the North of WA thenput it in here. If there are special accessories needed, mention them here and take them all into accountwhen you define the level of protection offered with your equipment.]

EQUIPMENTEquipment documentation is appropriate to the requirements of the location YES/NOEquipment compliance level [e.g. Ex ib IIC T4]Does equipment exceed hazard requirements [in this case YES]Is it certified to IECEx or ANZEx YES/NO

If YES quote certificate No: ___________________________

If NO, which standard? ___________________________

If NO above then has a Conformity Assessment been carried out for this location? YES/NOIf YES is the CAD signed and accepted by the site owner YES/NOAttach CAD if applicable to this sheet

If Equipment is not certified sufficiently to meet the requirement to operate safely in this hazardthen what steps are being taken to negate the risk? [This could be “a clearly defined operationalprocedure for areas of greater hazard where equipment use will be prohibited” e.g.

“Areas referenced on GHAC Drawing Ref xxx, dated, xx ,rev X indicates a Zone 0 area around xxxprocesses and plant yyy and these areas are to clearly marked with Yellow paint and signage toinsure that Ex ib IIB apparatus will not be carried into his area. Site operational procedures Ref xxhave also been included in the safety inductions for all staff to reflect this”]

Certainly a vendor would be foolish not to note their acceptance of the site hazard. If in doubt in thefirst instance ask the customer what is acceptable, most major sites have their own site OH&S rules.

If in doubt refer to a hazardous area assessor for comment.



Some small sites in particular have been loose in the application of EEHA standards but enforcementand acceptance of the rules is becoming more common every day. What the client thought was OKlast year might be different this year when an insurance assessor refuses re-insurance (this iscommon source of work for EEHA assessors) or WorkCover is called to an injury (most assessor’sdon’t want to get their work from this).

If in doubt ask…most assessors charge nothing for a few minutes on the phone, it can save you a lotof $.

Section 6: Appendices

APPENDIX A - Marking

AS/NZS60079.0 Clause 29.3 General States

“The marking shall include the following:

a) the name of the manufacturer or his registered trade mark;

b) the manufacturer's type identification;

c) a serial number

e) if it is necessary to indicate specific conditions of use, the symbol “X” shall be placed after thecertificate reference. An advisory marking may appear on the equipment as an alternative to therequirement for the “X” marking;

f) the specific Ex marking for explosive gas atmospheres, and/ or for explosive dust atmospheres. TheEx marking for explosive gas atmospheres and explosive dust atmospheres shall be separate and notcombined.



APPENDIX B IECEx Member Bodies

(from IECEx website, www.iecex.com)

IECEx Member Bodies

Country National Member Body Contact

Australia (AU)

Standards AustraliaMs Alisa NasicMs Ashwini SharmaLevel 10, 20 Bridge StSydney NSW 2000GPO Box 476Sydney NSW 2001

Tel: +61 2 9237 6171Free call within Australia:1800 035 822

Brazil (BR)COBEI – COMITÊ BRASILEIRO DE ELECTRICIDADE,ELETRÔNICA, ILUMINAÇÃO E TELECOMUNICAÇÕESMr José Sebastião VielAvenida Paulista no 1439 - 11o andar, conj. 114CEP 01311-200 - São PauloBrazil

Canada (CA)

Canadian National Committee (CANC/IEC)Mrs. Lynne GibbensStandards Council of CanadaProgram Manager, IEC and CANC/IEC SecretaryInternational Standards Development, Standards SolutionsBranch600-55 Metcalfe Street,Ottawa ON K1P 6L5CANADA

Tel: +1 613 238-3222,Ext. 452Fax: +1 613 569 7808

China (CN)

Certification and Accreditation Administration of thePeople's Republic of China (CNCA)Chinese National Committee of the IEC

Ms. Du ChunjingDeputy Director GeneralDepartment for International Cooperation, CNCA.9 Madian East Road, Haidian District,Beijing 100088PEOPLE'S REPUBLIC OF CHINA

and

Ms. Fang Yan

Director for Multilateral affairsDepartment for International Cooperation, CNCA

Ms Du ChunjingTel: 86-10-8226 2669Fax:86-10-8226 0819

and

Ms. Fang YanTel: +86-10-8226 2810Fax: +86-10-8226 0741

Croatia (HR)Ex-Agency (Agency for explosive atmospheres)On behalf of:Croatian Standards Institute

Mr. Stipo DerekBastijanova bb10000 Zagreb

Tel: +385 1 3667 260/112Fax: +385 1 3667 262



CROATIA

Czech Republic (CZ) Physical technical Testing InstituteMr Jaromir HrubyPikartska 7CZ 71607 Ostrava-RadvaniceCZECH REPUBLIC

Ph: +420 596232715Fx: +420 596232672

Denmark (DK)Fonden Dansk Standard | Danish Standards FoundationMr R NielsenPortland TowersGöteborg Plads 1DK-2150 Nordhav

Tel: +45 3996 6153Mob +45 5151 4319

Finland (FI)SESKO Standardization in FinlandMr Risto SulonenVTT Expert Services LtdOtakaari 7B, EspooP.O. Box 134(Särkiniementie 3), FI-00211

Tel: +358 20 722 6415Fax: +358 20 722 7042

France (FR)LCIE by delegation from theIEC NATIONAL COMMITTEE of FRANCEMs Marie-Elisabeth d'Ornano33 avenue du Général Leclerc BP 8F 92266 FONTENAY-AUX-ROSESFRANCE

Tel: +33 1 40 95 5519Fax: +33 1 40 95 5401

Germany (DE)

Deutsches Komitee der IECDKE Deutsche KommissionElektrotechnik Elektronik Informationstechnikim DIN und VDEDr. Gerhard ImgrundStresemannallee 15DE-60596 Frankfurt am MainGERMANY

Tel: + 49 69 6308 300Fax: +49 69 6308 9300

Hungary (HU)

ExVÁ Testing Station for Explosion Proof EquipmentCompany Limitedby delegation from MAGYAR SZABVÁNYÜGYI TESTÜLET(MSZT)Mr. János MüllnerH 1037 BUDAPESTMIKOVINY S.u. 2-4HUNGARY

Tel: +36 1 250 1720Fax:+36 1 250 1720

Israel (IL) The Standards Institution of IsraelMr Yaacov WACHTEL42 Levanon st.Tel-AvivISRAEL 69977

Tel: +972-3-6465121Fax: +972-3-6467610

India (IN)

Bureau of Indian StandardsMr S M Shahid9 Bahadur Shah Zafar MargNEW DELHI

Tel/Fax: +91 1123231903



110 002INDIA

Italy (IT)

CEI - Comitato Elettrotecnico ItalianoMrs Cristina TimòTechnical DirectorVia Saccardo, 920134 MilanoITALIA

Tel: +39 02 21006206

Fax:+39 0221006210

Japan (JP)

JISC c/o International Electrotechnology StandardizationDivision,Industrial Science and Technology Policy and EnvironmentBureau,Ministry of Economy, Trade and Industry (METI)Mr. Kazuhide Horisaka Mr.Tomonori Fukuta1-3-1 Kasumigaseki, Chiyoda-ku,100-8901 TokyoJAPAN

Tel: +81 3 3501 9287Fax: +81 3 3580 9631

Korea (KR)

Korean Agency for Technology and Standards (KATS)Mr. Jeong Euisik - Director of conformity assessmentdivision, KATS

Contact person: Ms. Min Hyemin(International coordinator of conformity assessmentdivision, KATS)93 Isu-ro, Maeng dong-myeon, Eumseong-gun,Chungcheongbuk-do,REPUBLIC OF KOREA Zip code: 369-811

Tel: +82 43 870 5487Fax: +82 43 870 5678

Malaysia (MY)Ms Ainal Fatiha Mohd NoorDepartment of Standards MalaysiaLevel 1&2, Block 2300,Century SquareJalan Usahawan, Cyberjaya63000 SelangorMALAYSIA

Tel: + 603 8319 1353Fax: +603 8319 1511

Netherlands (NL)Netherlands National Committee of the IECMr Willem WolfVlinderweg 6Post Box 5059NL 2600 GB DelftNETHERLANDS

Tel: +31 15 269 0208Fax: +31 15 269 0242

New Zealand (NZ) Standards New ZealandMr John KellyPrivate Bag 2439WellingtonNEW ZEALAND

Tel: +64 4 498 5990Fax: +64 4 498 5994

Norway (NO) Norsk Elektroteknisk Komite (NEK)Mr Birger HestnesManager DirectorMustads vei 10283 Oslo

Tel: +47 67 83 31 05Fax: +47 67 83 31 01



NORWAY

Poland (PL) Urzad Dozoru Technicznego (UDT)Dr Janusz Samula34, Szczesliwicka Street02-353 WarsawPOLAND

Tel: +48 22 57 22 149Fax: +48 22 57 22 244

Romania (RO) INSEMEX PETROSANIMr Constantin LUPUStr. General Vasile Milea nr.32-34Petrosani 2675ROMANIA

Tel: +40 2 54546277Fax:+40 2 54546277

Russia (RU)Federal Agency on Technical Regulating and Metrology(GOST)Mr A Zazhigalkin9 Leninsky ProspectMoscowB-49 GSP-1 119991RUSSIA

Tel: +7 499 236 0553

Fax:+7 499 236 4395

Singapore (SG)Spring SingaporeMr Jason LowSingapore National Committee of IECSolaris1 Fusionopolis Walk#01-02 South Tower, Solaris (Level 13)Singapore 138628

Tel: +65 6279 1813Fax:+65 6659 0639

Slovenia (SI) Slovenian Institute of Quality and MetrologyIgor LikarTrzaska cesta 2SI-1000 LjubljanaSLOVENIA

Tel: +386 1 4778 100Fax: +386 1 4778 444

South Africa (ZA)South African Flameproof AssociationOn behalf ofSouth African National Committee of the IECMr. Paul Meanwell12 Commercial RoadWadeville, 1428South Africa

Tel: +27 11 323 7012

Spain (ES)

LOM (Official Laboratory José María de Madariaga)On behalf of:AENOR (Spanish Association for Standardization andCertification)Mr Carlos Fernández Ramón (Managing Director)C/ Eric Kandel, 1 (Tecnogetafe)28906 Getafe (Madrid)Spain

Tel: + 34 91 442 13 66Fax: + 34 91 441 99 33

Sweden (SE)

SEKSEK Svensk ElstandardMr Ingvar ErikssonBox 1284SE-16429 KISTA

Tel: +46 8 444 14 16Fax: + 46 8 444 14 30



SWEDEN

Switzerland (CH) ElectrosuisseMr Fritz BeglingerElectrosuisseLuppmenstrasse 1CH-8320 FEHRALTORFSWITZERLAND

Tel: +41 44 956 1325Fax: +41 44 956 1825

Turkey (TR)Turkish Standards Institution (TSE)Ms Ebru BaliTurkish Standards Institution8780/1 Sok.No:5 CigliIZMIRTURKEY

Tel: +90 2323762425Fax: +90 2323861510

United Arab Emirates(AE)

Emirates Authority for Standardization and MetrologyESMA

H.E. Abdul Al Maeeni

Director General of ESMAP.O. Box 48666 Business Avenue BuildingEtihad Road, Deira, Dubai – UAE

P.O. Box 2166, 2nd Floor Ministry of Environment andWater Building,

Zayed Sports City, Abu Dhabi – UAE

Tel: + 971 4 2944434Fax: +971 4 2951898

United Kingdom (GB)

BEAMA Ltd by delegation from British ElectrotechnicalCommittee (Mr. Martin Danvers)

Mr. Raj VagdiaBeama LtdWestminster Tower3 Albert EmbankmentLondon SE1 78SLUNITED KINGDOM

Tel: +44 020 7793 3000

United States ofAmerica (US)

US National Committee of the IECExMr Joel SolisNEMA1300 North 17th StreetSuite 1847Rosslyn VA USA 22209UNITED STATES OF AMERICA

Tel: +1 703 841 3267Fax: +1 703 841 3367



APPENDIX C: Standards

The standards relevant to the technical requirements of Explosion Protected Electrical Equipment(EEHA) under the IECEx and ANZEx schemes are as follow, please NOTE: the Prefix “IEC” is replacedwith “AS/NZS” for the ANZEx equivalent:

IEC 60079-0 Part 0: Equipment - General requirements (GAS)IEC 60079-1 Part 1: Equipment protection by flameproof enclosures 'd'IEC 60079-2 Part 2: Equipment protection by pressurized enclosures 'p'IEC 60079-5 Part 5: Equipment protection by powder filling 'q'IEC 60079-6 Part 6: Equipment protection by oil immersion 'o'IEC 60079-7 Part 7: Equipment protection by increased safety 'e'IEC 60079-13 Part 13:Equipment protection by pressurised roomIEC 60079-11 Part 11: Equipment protection by intrinsic safety 'i'IEC 60079-15 Part 15:Construction, test and marking of type of protection "n" electrical apparatusIEC 60079-18 Part 18: Construction, test and marking of type of protection encapsulation "m"electrical apparatusIEC 60079.-19 Explosive Atmospheres Part 19: Equipment repair, overhaul and reclamationAS/NZS 3800:xxxx Electrical equipment for explosive atmospheres - Overhaul andRepairAS/NZS 4761 Competencies for working with electrical equipment for hazardous areas (EEHA)4761.1 Part 1: Competency Standards 4761.2 Part 2 Guide to assessing competencyIEC 60079-25 Part 25: Intrinsically safe systemsIEC 60079-26 Part 26: Equipment with equipment protection level (EPL) GaIEC 60079-27 Part 27: Field bus intrinsically safe concept (FISCO)IEC 60079-31 Part 31: Equipment dust ignition protection by enclosure "t"IEC 60079-35-1 Part 35-1: Cap lights for use in mines susceptible to firedamp - Generalrequirements - Construction and testing in relation to the risk of explosionAS/NZS 3800:1997 Electrical equipment for explosive atmospheres - Overhaul and repairIEC 61241-0 Part 0: General requirements (DUST)IEC 61241-1 Part 1: Protection by enclosures 'tD'IEC 61241-1-1 Part 1-1: Electrical apparatus protected by enclosures and surface temperaturelimitation - Section 1 - Specification for apparatusIEC 61241-4 Part 4: Protection by enclosures "tD"IEC 61241-11 Part 11: Protection by intrinsic safety 'iD'IEC 61241-18 Part 18: Protection by encapsulation "mD"IEC 62013-1 Cap lights for use in mines susceptible to firedamp - Part 1: General requirements -Construction and testing in relation to the risk of explosion



APPENDIX D: Regulatory Authorities

NSW

Workcover www.workcover.nsw.gov.au/health-and-safety/manage-workplace-safety/your-responsibilities

Department Trade and Investment; Division of Resourcesand Energy www.resourcesandenergy.nsw.gov.au/

NSW Fair Trading www.fairtrading.nsw.gov.au

VIC

Worksafe www.worksafe.vic.gov.au

Energy Safe Victoria www.esv.vic.gov.au

QLD

WorkCover QLD https://www.worksafe.qld.gov.au/

QLD Electrical Safety Office www.eso.qld.gov.au

QLD Department of Mines and Energy www.dme.qld.gov.au

TAS

Workcover www.workcover.tas.gov.au

TAS Department of Justice www.justice.tas.gov.au

SA

SA Office of the Technical Regulator www.technicalregulator.sa.gov.au

SafeWork www.safework.sa.gov.au

SA Office of Consumer & Business www.ocba.sa.gov.au

WA

Energy Safety WA www.energysafety.wa.gov.au

Workcover www.workcover.wa.gov.au

NT

WorkSafe www.worksafe.nt.gov.auACTWorkSafe www.worksafe.act.gov.au

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA)

NOPSEMA is a Commonwealth statutory agency regulating the health and safety, structural integrity,and environmental management of all offshore petroleum facilities in Commonwealth waters, and incoastal waters where state powers have been conferred.

Contact details: www.nopsema.gov.au



APPENDIX E: Old Standards and Certificates

Equipment which was compliant at the time of purchase by the end user is allowed to continue inservice without a time limit. Vendors however are not allowed to sell new equipment as compliantafter the expiry of the original certificate. Older AUSEx certificates were issued with an expiry datenewer IECEx and ANZEx certificates do not have expiry dates as they are subject to ongoing qualityaudits by the standards body.

The original AUSEx standards we not required to have ongoing quality audits.

Similarly where the rules change, e.g. the requirement for intrinsically safe equipment to be dustrated with a “D” suffix; the original equipment if purchased prior to the change in rules is allowableindefinitely subject to changes in the site hazard or another external factors but new equipmentwith the now incorrect marking and certification cannot be used, even if it is the same modelwithout a comprehensive risk assessment..

AS/NZS 2381.1:2005Electrical equipment for explosive gas atmospheres - Selection, installation and maintenance -General requirements with amendments through to 2007 was replaced by AS/NZS60079.14.

AS 2381.7-1989Electrical equipment for explosive atmospheres - Selection, installation and maintenance - Intrinsicsafety was first issued in 1980 as part of a series of Standards on explosion-protection techniquesand was based on IEC 60079-0. The third edition of AS 2380.1, published in 1989, is similar to thecorresponding requirements contained in AS/NZS 60079.0 and AS/NZS60079.14 and from there onAustralia totally adopted the IEC equivalent standard.

Some other standards which might be found in the system, all replaced now with the IECEx schemestandards.

Ex s (Special Protection) Apparatus Standards: AS/NZS 1826(Int) and AS 1076.8 Ex d (Flameproof)Apparatus Standard AS 2380.2 Installation Standards AS/NZS 2381.2

Electrical equipment for explosive atmospheres - Selection, installation and maintenance -Flameproof enclosure 'd'

Ex e (Increased Safety)Apparatus Standards AS 2380.6 Installation Standards AS2381.6 Ex p (Pressurisation)-when installed to Zone 1 requirements apparatus Standard AS2380.4 Ex v (Ventilation. Apparatus Standards AS 1482 Ex n (Non-incendive) Apparatus Standard AS1076.7

AS/NZS 2430.X series standards were the predecessors of the hazardous area classificationstandards AS/NZS60079.10.1 (GAS) and AS/NZS60079.10.2 (DUST).



APPENDIX F: Frequently Asked Questions (FAQ’s)

Intrinsic Safety

QUESTION: What does “I.S.” or “intrinsically safe” mean in terms of a description for electricalequipment?

Answer:

Intrinsic safety “Ex i” is one of a number of a hazardous area protection techniques. Not allequipment uses this technique.

It is a protection method based on the restriction of electrical energy within the device (apparatus)and of any interconnecting wiring to a level below that which can cause ignition by either sparking orheating effects.

Equipment using this technique is “intrinsically safe” in the true definition of the phrase, i.e. It issafe under any specified condition because it does NOT have enough energy or heating effect toignite the gas or dust (Ex ia/b/cD) even under fault conditions.

Zones

QUESTION: What is the difference between the zones in the Australian hazardous area classificationsystem?

Answer:

Zone 0:an area in which an explosive gas atmosphere is present continuously or is present for longperiods.

Zone 1:an area in which an explosive gas atmosphere is likely to occur periodically in normaloperation.

Zone 2:an area in which an explosive gas atmosphere is not likely to occur in normal operation and ifit does occur it will exist for a short period only.

Zone 20: An area in which combustible dust, as a cloud, is present continuously or frequently, duringnormal operation, in sufficient quantity to be capable of producing an explosive concentration ofcombustible dust mixed with air, and/or where layers of dust of uncontrollable and excessivethickness can be formed.

Zone 21: An area in which combustible dust, as a cloud, is likely to occur during normal operation, insufficient quantities to be capable of producing an explosive concentration of combustible dustmixed with air.

Zone 22: Areas in which combustible dust clouds may occur infrequently, and persist for only a shortperiod, or in which accumulations or layers of combustible dust may be present under abnormalconditions and give rise to combustible mixtures of dust in air.

QUESTION: How big are the actual hazardous areas?

Answer:

Sometime quite small 1-2 metres but for ease of management a site owner and those defining thehazard often include whole areas. Typically inside of building where the gas or dust is contained willbe given a “blanket” allocation. If in doubt ask the site owner.



US Equipment Label (Marking)

QUESTION: The certified versions of the portable radios I wish to use are described as being:

“Intrinsically Safe for Class I, II, III Division 1, Groups C, D, E, F, and G hazardous (classified) locationsand suitable for Class I, Division 2, Groups A, B, C and D hazardous (classified) locations.Temperature “T” rating T3C.”

What does this actually mean?

Answer: Intrinsic safety is the technique applied to protect the device (apparatus)

Division 1 (in the US NEC 500 scheme) is similar in definition to IECEx/ANZEx Zone 0 and Zone 1.

Under the Australian scheme however Zone 0 carries a few more conditions. Therefore it can onlybe considered as comparable to Zone 1 (subject to a more detailed specific assessment of theproduct/s and hazard/s).

Class I – GAS, Class II – DUST, Class III – FLYINGS. The handset therefore is suitable for all US defined“Classes” or in Australian terms: Gas and Dust (but not underground mining).

Group C, Ethylene (Australian Group IIB) Group D, Propane (Australian Group IIA), Group E, MetalDusts (Australian Group IIIC), Group F, Carbonaceous Dusts and Group G, Combustible Dusts. NoteGroup F and G are not related to the Australian dust grouping system which is based on electricalconductivity.

US NEC 500 Temperature class T3C is 160°C which is a lower (better) surface temperature than ourAustralian T3 temperature rating of 200°C in the IECEx and ANZEx schemes.

This equates to Zone 1 IIB T3 and Zone 2 IIC T3 (T3 is worst case) in the ANZEx and IECExschemes.

And in Division 2 (Zone 2) it is tested as safe in NEC Groups A and B (Acetylene and Hydrogen)

This equates to Zone 2 IIC T160°C in the IECEx and ANZEx schemes.

This is only for comparison purposes it cannot be put into service in Australia without a formalconformity assessment provided by a competent hazardous area assessor.

NOTE: The NEC 500 system allows different gas and dust groups in each Zone (Division) whereasIECEx and ANZEx do not.

IECEX/ANZEx Marking/Labelling

QUESTION: How can I identify whether the device is certified?

Answer:

The equipment label called the marking MUST include the following:

name of the manufacturer or his registered trade mark; manufacturer's type identification; serial number, except for connection accessories and very small electrical equipment on

which there is limited space; the name or mark of the certificate issuer and the certificate reference in the following form:

the last two figures of the year of the certificate followed by a “.” followed by a unique fourcharacter reference for the certificate in that year;

If there are specific conditions of use, the symbol “X” shall be placed after the certificatereference. An advisory marking may appear on the equipment as an alternative to therequirement for the “X” marking;

Check IECEx certificates at www.iecex.com and ANZEx at www.anzex.com.au



Label and Certificate not the same?

The label on the FM approved radio states it is only suitable for Division 1 whereas the certificatesays Division 2 as well, is this right?

Answer: YES

In the Australian system under IECEx or ANZEx the marking (i.e. label) on the product must show theexact details of the protection levels applicable (as well as other info, see “Marking” Page26) withsome minor exemptions where the label is not sufficiently large enough to show all of the details.The US and Canadian NEC 500 system allows the description to be abbreviated.

IMPORTANT that you check and be sure that the certified device is the one actually on thecertificates; this means the part number MUST be completely itemised in the certificate, not a "closeenough" number or a digit different, it MUST be exactly as shown on the compliance papers or it isNOT certified (regardless of what the vendor or manufacturer says). If it has been added after theoriginal certificate has been issued then there WILL be a document from the certifying body provingthat.

Fixed Radio System Equipment

QUESTION: Do base stations and other fixed equipment need hazardous area compliance?

Answer: Only if they are installed in a hazardous area (This is unlikely and would be highly unusual).

Typically mains powered equipment is not installed in hazardous areas unless it is absolutelynecessary, e.g. with motors driving pumps necessary to the operation of the plant and wherelocation is not flexible. The cost of certifying these electrically high powered devices is very high andrequires specialised techniques (generally not including intrinsic safety). Similarly with batterychargers; rarely will you find mains power outlets in hazardous areas and if so they are strictlycontrolled. Charging is limited to being done in NON hazardous areas such as plant room andsecurity gate houses.

It is possible that the building will be certified using some form or protection (ventilation orpressurisation are common) and this will make the interior a NON hazardous area.

The site owner should be able to define safe areas for installation of non-certified equipment, if indoubt refer to the site hazardous area classification drawings.

Change Batteries on Portable Equipment

QUESTION: Can I change batteries in a hazardous environment?

Answer: Generally NO.

It is common for the “Special Conditions” on the certificate to include a statement like” Batteriesmust not be removed or charged in hazardous areas” If in doubt then NO.

Engrave or label equipment

QUESTION: Can I engrave the housing of a portable device with serial number or plant details?

Answer: No.

Impact testing is a mandatory part of the compliance testing for all equipment. The housing, if madeof nonconductive materials (e.g. plastics of whatever form) must meet the defined requirements forsuch enclosures and altering the characteristics in any way (static charge build up, surface area,impact resistance) may compromise this testing. It is normally acceptable to have a glued plasticlabel less than 50mm x 50mm (for a Group IIB Environment) attached to the handset. Refer:AS/NZS60079.0 Table 6 for more info.



Similarly PAINTING of the handsets is not acceptable as it may compromise the electrostaticdischarge characteristics of the enclosure.

Regular Inspections

QUESTION: Do portable radios and similar portable equipment need regular re-inspection?

Answer: YES

The Applicable standard AS/NZS60079.17 states:

“Clause 4.4.3 Moveable equipment

Movable electrical equipment (hand-held, portable, and transportable) is particularly prone todamage or misuse and therefore the interval between periodic inspections may need to be reduced.Movable electrical equipment shall be submitted to a close inspection at least every 12 months.Enclosures which are frequently opened (such as battery housings) shall be given a detailedinspection at least every 6 months. In addition, the equipment shall be visually checked by the user,before use, to ensure that the equipment is not obviously damaged.”

Experience though indicates that annual inspections are most common and they appear adequatefor most sites.

Foreign Certified Equipment

QUESTION: If the equipment is certified to a foreign standard does it need to meet the Australianrequirements for inspections?

Answer: YES

A Conformity Assessment allowing use of foreign standard equipment is simply an assessment of theforeign standard against the Australian compliance rules; it is not an exemption for any of thenormal operating safety requirements.

QUESTION: Is it Illegal to Supply Foreign Certified Equipment?

Answer: NO providing as you do not supply product that is unsafe or unfit for the purpose intended.

Approval for Foreign Equipment, site specific

QUESTION: Can I use a Conformity Assessment Document (CAD) or Letter of No Objection from aregulatory body to use the equipment on similar hazardous site?

Answer: NO

Conformity assessments compare the product certification to the Australian regulations in term ofthe identified risk on that specific site. CAD’s (and letters of no objection) are site and productspecific. Approval for use on one site has no relevance and is invalid on another site even if thehazards are same or similar.

Repairers and Inspectors

QUESTION: Do repairers need to be qualified as inspectors?

Answer: NO.

Under AS/NZS3800 the repairer is qualified to inspect for return to service and will providedocumentation to that effect. If the equipment is foreign certified it will need to be re-inspectedprior to being returned to service.



Servicing and Repair

QUESTION: Who can service hazardous area equipment?

Answer:

Australian and IECEx certified equipment must be serviced by workshops suitable qualified andcertified to AS/NZS3800. IECEx certified equipment must be serviced and repaired under IECEX rulesas defined in IEC60079.19.

Foreign certified equipment must be serviced/repaired in accordance with the rules applied by theforeign certifying body or if it can be achieved by use of an AS/NZS3800 approved workshop. Notethat most manufacturers will not provide sufficient service and repair data for 3rd party repairers tomeet the demands of the standard.

FM Approvals have a mandatory requirement for workshops servicing and repairing FM Approvedcommunications equipment. The Standard is described as “Class Number 3605” and the workshop/sis/are subject to external audit as with the ANZEx scheme. See below:

The FM 3600 standard is quoted as below:

1.1 Purpose

This standard serves as the basis for FM Approval of independently owned facilities that repair FMApproved communication equipment for hazardous (classified) locations.

1.2 Scope

This standard does not apply:

when modifications are made to the equipment; when an FM Approval label is applied to equipment not shipped from the original

manufacturer as FM Approved; to repairs made by facilities owned by the original manufacturer.

The manufacturer’s repair facilities are covered by the Approval Agreement for the listed product.That Agreement requires the manufacturer to provide adequate facilities for repair of the listedproduct.

Items not considered as repairs are those in which an action is performed on a unit whichdoes not require the outer casing of the unit to be opened in a manner which exposes theinternal electrical circuits of the unit. The following is a partial list of examples which are notconsidered to be repairs:

replacement of an antenna, changing an external accessory, changing/replacement of a battery pack, software loaded into the unit, a control knob, escutcheon, or, belt clip”



Damaged Equipment

QUESTION: What should a user of say a handset that is physically damaged do?

Answer:

Any certified hazardous area equipment showing signs of damage must be immediately removedfrom the hazardous environment and not returned to service until after repairs and re-inspectionare carried out.

It does not need an inspector to identify broken housings, display screens, battery assemblies orantenna. If its damaged it’s not safe and must be removed from service.

Inspectors

QUESTION: Who can inspect hazardous area equipment?

Answer:

Only those persons deemed competent under the rules of AS/NZS60079.17 and tested against thecompetencies listed in AS/NZS4761.

Radio Transmission, Ignition?

QUESTION: Can Radio transmissions ignite hazardous materials?

Answer: The standards define the maximum RF parameters as follows:

From AS/NZS60079.0 Clause 6.6.1 Radio frequency sources

Quote “The threshold power of radio frequency (9 kHz to 60 GHz) for continuous transmissions andfor pulsed transmissions whose pulse durations exceed the thermal initiation time shall not exceedthe values shown in Table 4. Programmable or software control intended for setting by the user shallnot be permitted.” Unquote

Radio frequency power thresholdsGas Group Power in Watts Thermal Initiation TimeGroup1 (Mining) 6.0W 200µSecsGroup IIA (Propane) 6.0W 100 µSecsGroup IIB (Ethylene) 3.5W 80 µSecsGroup IIC (Hydrogen) 2.0W 20 µSecsGroup III (Dust) 6.0W 200 µSecs

Device (Apparatus) Certificate with a “U” Suffix

QUESTION: I have a device with a certificate with a “U” Suffix, can I use it?

Answer: NO.

An Ex component certificate, identified by the symbol “U” suffix to the certificate number is for partsof equipment that are incomplete and require further evaluation prior to incorporation in Exequipment. It is NOT a fully certified device.



Device (Apparatus) Certificate with an “X” Suffix

QUESTION: I have a device with a certificate with a “X” Suffix, can I use it?

Answer: YES.

The “X” indicates “special conditions” which will be identified on the certificate of compliance, if youmeet the “Special conditions” and the apparatus is suitable in all other aspect then YES you can useit. “X” suffix is common on portable equipment, e.g. conditions may include mandatory use ofleather carry cases or define where a device can be charged, Read the conditions and follow them,they are NOT negotiable.

Power Limitation on Radios

QUESTION: I’ve heard that IECEx radios must be limited to 1 watt. Is this true?

Answer: NO.

This is not a specific factor in the compliance and if this condition is relevant to the handset/s youare using then it will either be dictated by the model number or a special condition on thecertificate.

A lot of products are limited to this power output level but the limitation is the result of other testedparameters. If the handset uses excessive power which may cause ignition (power=heat=ignition) athigher output level then it may be necessary to limit the device to meet the other parameters intesting.

Let’s assume a highly efficient radio can transmit at say 3 watts and a less efficient radio uses thesame source power to generate 1 watt then the lesser efficient handset may well be controlled tothe lower output power as part of its technical requirement to meet the testing parameters.

FM approved equipment has often higher RF output level than IECEx and ATEX (European)certification because FM has different source power levels for the same level of protection.

This in one of the reasons why a detailed conformity assessment is needed. The standards aresimply not the same.

Site Examples

NOTE: PLEASE TREAT THIS WITH CAUTION. Site rules override general assumptions; the site ownerhas the right to vary these classifications. Do not assume this is correct for the specific site on whichyou are working. Some sites have chemicals used in the process which may well exceed theexplosivity levels of the end product they produce.

Do not underestimate the dangers of explosive dusts.

Assessment should always be done in reference to the customer’s site specific hazardous areaclassification drawings or at a minimum ask the customer or refer to an EEHA Assessor.

The Australian (and IEC) standard for defining specific ignition factors for all chemicals is AS/NZS60079.20.1:2012 or IEC 60079-20-1, Ed. 1.0 (2010)Explosive atmospheres Part 20.1: Materialcharacteristics for gas and vapour classification—Test methods and data.

Fuel terminal that handles petroleum fuels only (including petrol and diesel) will normally be IIA T3,BUT for various reasons which we cannot argue some fuel operators demand IIB T3, their choice.Ask the customer,

LNG plant of storage is typically Propane IIA T2 with a minimum ignition temp of 450C

Airport refuelling operations including JET A1 and Avgas, usually IIA T3.

Grain Processing for oils such as canola and biodiesel usually (not always) uses Hexane at IIA T3.



Crude oil refining, ask, if a refinery in this country doesn’t have a clear definition of its risks it won’thave a licence to operate.

Mistakes

Example Carbonyl Sulphide is IIA T3 is NOT the same Carbon Disulfide is IIC T6

Carbon disulphide has an auto ignition temp of 90°C and a spark ignition level of 9 mJoules.

Carbonyl sulphide has an auto ignition temperature of 209°C and a spark ignition level of 260mJoules.

Typical Drawings

The following drawings are for reference only and specific conditions relating to unique sites,vehicles or machinery have not been taken into account. The drawings are conceptual only providean indication of what a typical hazard might look like. The second two (2) drawings are copied fromthe old (now replaced) Australian standards AS/NZS 2430.3.3.2:2004 and AS/NZS 2430.3.3:2004.

Figure 4: Typical Plan View of Aircraft Re-Fuelling Operation



Figure 5: Road or Rail Tanker Loading Without Vapour Recovery (Example ONLY)

Figure 6: Exterior of Fuel Dispensing unit in Adequately Ventilated Area (Example ONLY)

Where do you find EEHA Assessors?

Most clients already have established relationships with an EEHA assessor. This is the best option;he/she should already know the site rules and hazards and much time and money will be saved byutilising this expertise and experience.

Some small sites will have no established assessor relationship, many are new to the regulations andmost commonly companies who preferred to limit their involvement in this area are now forced toact as the regulatory system becomes more onerous. Many site owners are wary of having a newassessor/inspector on site in fear that he/she might find some major works needs immediate andexpensive attention. Some consider the assessor may take problem to WorkCover, this would rarelyhappen unless a disaster was imminent in which case it would be their best option anyway.Assessors make a living out of fixing problems not reporting clients to regulatory authorities.



The internet will provide names and contacts. The controlling factor is whether the assessor has thecorrect qualifications as prescribed in AS/NZS 4761.1:2008 “Competencies for working with electricalequipment for hazardous areas (EEHA) - Competency Standards“.

Any people who have the competences prescribed AS/NZS4761: can do the work. Most electriciansworking in hazardous areas can do inspections. Most however limit themselves to doing installationof electrical equipment and have limited exposure to portable equipment.

Most electricians working in hazardous areas have some of the competencies necessary to adviseyou whether you are using the correct equipment.

The following was obtained from the web and this is not a recommendation only a guide as to whoadvertise suitable services:

DCA ExtechPO Box 605 Albury, NSW 2640 - Mobile: 0407 254 975 Fax: 0260 210208

Explosion Protection Technology8 Kirkfell Court, Berwick,VIC 3806 - Tel/Fax: 0397073110

E-x Solutions International Pty LtdPO Box 2010, Forest Hill VIC 3131Tel: 0882702177 - Mobile 0433 232 013

TexecoAddress: Unit 20 / 87 McLarty Ave, Joondalup WA6027 - Phone: 08 9409 1130, Mobile: 0438 000512

Also most large electrical contracting companies have EEHA assessors either on staff or as regularcontractors including Downers, Electrical Design and Construction (EDC), Sage Consulting, ConsoftAutomation.



History

The author was originally trained as a radio technician with the Defence Department, later movinginto sales roles in number of major two-way radio companies.

The late 1980’s brought about a demand for major upgrades to most of the Australian oil refineriesand the author’s technical background and supply knowledge of the radio communications industryafforded opportunities to become a part of this exciting work. While most of us involved did notrecognise this at the time, this was to be the last of major investment in oil refining in Australia. SEAsia very quickly dominated the downstream supply of petroleum products in the 1990’s and thehigh operating costs and environmental constraints here in Australia made the domestic industryless and less viable.

However the late 1980’s was a boom time and a lucrative contract as a communications consultantwith Caltex Refining Australia in Australia and then the Sydney Petroleum Pipeline, led to over adecade of small contracts on the same type with Shell Refining at Clyde and Geelong. The mostexciting part was overseas contracts in the USA, with Caltex Services Corporation as a consultant onthe Star Petroleum Refining Project in Thailand and an upgrade of an old refinery at Betangas in thePhilippines. Little did we know but we were building and upgrading some of the refineries whichwould ultimately displace the Australian refineries.

Ultimately reductions in refinery work led to opportunities in equipment design and proudly thedevelopment of the first certified intrinsically safe mobile telephone in 2004. This led to a careerchange; since then have been active in design of various certified apparatus. This work still continuestoday.

Part of the process needed to fully understand the design requirements for intrinsically safeequipment led to completion of the EEHA inspection course through NSW TAFE in 2004. Thiseducation process is continuing as it must do in the fast moving world of electronics. Currently Ihave enrolled to upgrade my qualifications to gain the latest required competencies for conformityassessment of foreign certified equipment for both gas and dust environments.

The document was prepared by Gary Devlin, DCA-Extech.

Tel: +61 407 254975Fax: +61 260 210208Email: [email protected]: www.dca-extech.com.au

Document version information

Version Date Variation Author

1.0 14/01/2016 Initial document from DCA-Extech G Devlin

1.1 25/01/2016 ARCIA identification & copyright tag added I Miller